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                              SDCC ASxxxx Assemblers


                                       and


                          SDCC ASLINK Relocating Linker


        CHAPTER 1  THE ASSEMBLER                                     1-1
          1.1     THE ASXXXX ASSEMBLERS                              1-1
          1.1.1     Assembly Pass 1                                  1-2
          1.1.2     Assembly Pass 2                                  1-2
          1.1.3     Assembly Pass 3                                  1-2
          1.2     SOURCE PROGRAM FORMAT                              1-3
          1.2.1     Statement Format                                 1-3
          1.2.1.1     Label Field                                    1-3
          1.2.1.2     Operator Field                                 1-5
          1.2.1.3     Operand Field                                  1-5
          1.2.1.4     Comment Field                                  1-6
          1.3     SYMBOLS AND EXPRESSIONS                            1-6
          1.3.1     Character Set                                    1-6
          1.3.2     User-Defined Symbols                            1-10
          1.3.3     Reusable Symbols                                1-10 
          1.3.4     Current Location Counter                        1-12
          1.3.5     Numbers                                         1-13 
          1.3.6     Terms                                           1-14
          1.3.7     Expressions                                     1-14 
          1.4     GENERAL ASSEMBLER DIRECTIVES                      1-16
          1.4.1     .module Directive                               1-16
          1.4.2     .title Directive                                1-16 
          1.4.3     .sbttl Directive                                1-17
          1.4.4     .list and .nlist Directives                     1-17 
          1.4.5     .page Directive                                 1-18
          1.4.8     .byte, .db, and .fcb Directives                 1-20
          1.4.9     .word, .dw, and .fdb Directives                 1-21 
          1.4.10    .3byte and .triple Directives                   1-21 
          1.4.11    .4byte and .quad Directive                      1-22 
          1.4.12    .blkb, .ds, .rmb, and .rs Directives            1-22 
          1.4.13    .blkw, .blk3, and .blk4 Directives              1-22 
          1.4.14    .ascii, .str, and .fcc Directives               1-23 
          1.4.15    .ascis and .strs Directives                     1-23 
          1.4.16    .asciz and .strz Directives                     1-24 
          1.4.18    .radix Directive                                1-25
          1.4.19    .even Directive                                 1-25
          1.4.20    .odd Directive                                  1-25
          1.4.21    .bndry Directive                                1-26 
          1.4.22    .area Directive                                 1-27 
          1.4.24    .org Directive                                  1-30 
          1.4.25    .globl Directive                                1-31 
          1.4.26    .local Directive                                1-31 
          1.4.27    .equ, .gblequ, and .lclequ Directives           1-32 
          1.4.28    .if, .else, and .endif Directives               1-33 
          1.4.29    .iff, .ift, and .iftf Directives                1-34 
          1.4.30    .ifxx Directives                                1-35 
          1.4.31    .ifdef Directive                                1-36 
          1.4.32    .ifndef Directive                               1-37 
          1.4.33    .ifb Directive                                  1-38 
          1.4.34    .ifnb Directive                                 1-39 
          1.4.35    .ifidn Directive                                1-40 
          1.4.36    .ifdif Directive                                1-41 


                                                                 Page ii



          1.4.37    Alternate .if Directive Forms                   1-42 
          1.4.38    Immediate Conditional Assembly Directives       1-43 
          1.4.39    .include Directive                              1-44
          1.4.40    .define and .undefine Directives                1-45 
          1.4.41    .setdp Directive                                1-46 
          1.4.42    .16bit, .24bit, and .32bit Directives           1-48 
          1.4.45    .end Directive                                  1-49 
          1.5     INVOKING ASXXXX                                   1-50
          1.6     ERRORS                                            1-52
          1.7     LISTING FILE                                      1-54
          1.8     SYMBOL TABLE FILE                                 1-56
          1.9     OBJECT FILE                                       1-57

        CHAPTER 2  THE MACRO PROCESSOR                               2-1 
          2.1     DEFINING MACROS                                    2-1 
          2.1.1     .macro Directive                                 2-2 
          2.1.2     .endm Directive                                  2-3 
          2.1.3     .mexit Directive                                 2-3 
          2.2     CALLING MACROS                                     2-4 
          2.3     ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS     2-5 
          2.3.1     Macro Nesting                                    2-6 
          2.3.2     Special Characters in Macro Arguments            2-7 
          2.3.3     Passing Numerical Arguments as Symbols           2-7 
          2.3.4     Number of Arguments in Macro Calls               2-9 
          2.3.5     Creating Local Symbols Automatically             2-9 
          2.3.6     Concatenation of Macro Arguments                2-10 
          2.4     MACRO ATTRIBUTE DIRECTIVES                        2-11 
          2.4.1     .narg Directive                                 2-12 
          2.4.2     .nchr Directive                                 2-13 
          2.4.3     .ntyp Directive                                 2-14 
          2.4.4     .nval Directive                                 2-14 
          2.5     INDEFINITE REPEAT BLOCK DIRECTIVES                2-15 
          2.5.1     .irp Directive                                  2-16 
          2.5.2     .irpc Directive                                 2-17 
          2.6     REPEAT BLOCK DIRECTIVE                            2-18 
          2.6.1     .rept                                           2-18 
          2.7     MACRO DELETION DIRECTIVE                          2-19 
          2.7.1     .mdelete                                        2-19 
          2.8     MACRO INVOCATION DETAILS                          2-19 
          2.9     BUILDING A MACRO LIBRARY                          2-20 
          2.9.1     .mlib Macro Directive                           2-21 
          2.9.2     .mcall Macro Directive                          2-22 
          2.10    EXAMPLE MACRO CROSS ASSEMBLERS                    2-24 

        CHAPTER 3  THE LINKER                                        3-1
          3.1     ASLINK RELOCATING LINKER                           3-1
          3.2     INVOKING ASLINK                                    3-2
          3.3     LIBRARY PATH(S) AND FILE(S)                        3-5
          3.4     ASLINK PROCESSING                                  3-6


                                                                Page iii



          3.6     ASXXXX VERSION 3.XX LINKING                       3-15 
          3.6.1     Object Module Format                            3-15
          3.6.2     Header Line                                     3-15
          3.6.3     Module Line                                     3-16
          3.6.4     Area Line                                       3-16
          3.6.5     Symbol Line                                     3-16
          3.6.6     T Line                                          3-16
          3.6.7     R Line                                          3-17
          3.6.8     P Line                                          3-17
          3.6.9     24-Bit and 32-Bit Addressing                    3-18 
          3.6.10    ASlink V3.xx Error Messages                     3-18 
          3.7     INTEL IHX OUTPUT FORMAT (16-BIT)                  3-21 
          3.8     INTEL I86 OUTPUT FORMAT (24 OR 32-BIT)            3-22 
          3.9     MOTORLA S1-S9 OUTPUT FORMAT (16-BIT)              3-23 

        CHAPTER 4  BUILDING ASXXXX AND ASLINK                        4-1 
          4.1     BUILDING ASXXXX AND ASLINK WITH LINUX              4-2 
          4.2     BUILDING ASXXXX AND ASLINK UNDER CYGWIN            4-2 
          4.3     BUILDING ASXXXX AND ASLINK WITH DJGPP              4-3 
          4.4     BUILDING ASXXXX AND ASLINK WITH BORLAND'S
                  TURBO C++ 3.0                                      4-3 
          4.4.1     Graphical User Interface                         4-3 
          4.4.2     Command Line Interface                           4-4 
          4.5     BUILDING ASXXXX AND ASLINK WITH
                  MS VISUAL C++ 6.0                                  4-5 
          4.5.1     Graphical User Interface                         4-5 
          4.5.2     Command Line Interface                           4-5 
          4.6     BUILDING ASXXXX AND ASLINK WITH
                  MS VISUAL STUDIO 2005                              4-6 
          4.6.1     Graphical User Interface                         4-6 
          4.6.2     Command Line Interface                           4-6 
          4.7     BUILDING ASXXXX AND ASLINK WITH
                  MS VISUAL STUDIO 2010                              4-7 
          4.7.1     Graphical User Interface                         4-7 
          4.7.2     Command Line Interface                           4-7 
          4.8     BUILDING ASXXXX AND ASLINK WITH
                  OPEN WATCOM V1.9                                   4-8 


                                                                 Page iv
        


          4.8.1     Graphical User Interface                         4-8 
          4.8.2     Command Line Interface                           4-8 
          4.9     BUILDING ASXXXX AND ASLINK WITH
                  SYMANTEC C/C++ V7.2                                4-9 
          4.9.1     Graphical User Interface                         4-9 
          4.9.2     Command Line Interface                           4-9 
          4.10    THE _CLEAN.BAT AND _PREP.BAT FILES                4-10 


        APPENDIX AK  AS68(HC[S])08 ASSEMBLER                        AK-1 
          AK.1    PROCESSOR SPECIFIC DIRECTIVES                     AK-1 
          AK.1.1    .hc08 Directive                                 AK-1 
          AK.1.2    .hcs08 Directive                                AK-1 
          AK.1.3    .6805 Directive                                 AK-2 
          AK.1.4    .hc05 Directive                                 AK-2 
          AK.1.5    The .__.CPU.  Variable                          AK-2 
          AK.2    68HC(S)08 REGISTER SET                            AK-3 
          AK.3    68HC(S)08 INSTRUCTION SET                         AK-3 
          AK.3.1    Control Instructions                            AK-4 
          AK.3.2    Bit Manipulation Instructions                   AK-4 
          AK.3.3    Branch Instructions                             AK-4 
          AK.3.4    Complex Branch Instructions                     AK-5 
          AK.3.5    Read-Modify-Write Instructions                  AK-5 
          AK.3.6    Register\Memory Instructions                    AK-6 
          AK.3.7    Double Operand Move Instruction                 AK-6 
          AK.3.8    16-Bit <H:X> Index Register Instructions        AK-6 
          AK.3.9    Jump and Jump to Subroutine Instructions        AK-6 



                                                                 Page ix
        


        APPENDIX AR  AS8051 ASSEMBLER                               AR-1 
          AR.1    ACKNOWLEDGMENT                                    AR-1 
          AR.2    8051 REGISTER SET                                 AR-1 
          AR.3    8051 INSTRUCTION SET                              AR-2 
          AR.3.1    Inherent Instructions                           AR-2 
          AR.3.2    Move Instructions                               AR-3 
          AR.3.3    Single Operand Instructions                     AR-3 
          AR.3.4    Two Operand Instructions                        AR-4 
          AR.3.5    Call and Return Instructions                    AR-4 
          AR.3.6    Jump Instructions                               AR-4 
          AR.3.7    Predefined Symbols:  SFR Map                    AR-5 
          AR.3.8    Predefined Symbols:  SFR Bit Addresses          AR-6 
          AR.3.9    Predefined Symbols:  Control Bits               AR-7 


                                                                  Page x
        


        APPENDIX AT  AS8XCXXX ASSEMBLER                             AT-1 
          AT.1    ACKNOWLEDGMENTS                                   AT-1 
          AT.2    AS8XCXXX ASSEMBLER DIRECTIVES                     AT-1 
          AT.2.1    Processor Selection Directives                  AT-1 
          AT.2.2    .cpu Directive                                  AT-2 
          AT.2.3    Processor Addressing Range Directives           AT-3 
          AT.2.4    The .__.CPU.  Variable                          AT-3 
          AT.2.5    DS80C390 Addressing Mode Directive              AT-4 
          AT.2.6    The .msb Directive                              AT-4 
          AT.3    DS8XCXXX REGISTER SET                             AT-6 
          AT.4    DS8XCXXX INSTRUCTION SET                          AT-6 
          AT.4.1    Inherent Instructions                           AT-7 
          AT.4.2    Move Instructions                               AT-7 
          AT.4.3    Single Operand Instructions                     AT-7 
          AT.4.4    Two Operand Instructions                        AT-8 
          AT.4.5    Call and Return Instructions                    AT-8 
          AT.4.6    Jump Instructions                               AT-8 
          AT.5    DS8XCXXX SPECIAL FUNCTION REGISTERS               AT-9 
          AT.5.1    SFR Map                                         AT-9 
          AT.5.2    Bit Addressable Registers:  Generic            AT-10 
          AT.5.3    Bit Addressable Registers:  Specific           AT-11 
          AT.5.4    Optional Symbols:  Control Bits                AT-12 
          AT.6    DS80C310 SPECIAL FUNCTION REGISTERS              AT-13 
          AT.6.1    SFR Map                                        AT-13 
          AT.6.2    Bit Addressable Registers:  Generic            AT-14 
          AT.6.3    Bit Addressable Registers:  Specific           AT-15 
          AT.6.4    Optional Symbols:  Control Bits                AT-16 
          AT.7    DS80C320/DS80C323 SPECIAL FUNCTION REGISTERS     AT-17 
          AT.7.1    SFR Map                                        AT-17 
          AT.7.2    Bit Addressable Registers:  Generic            AT-18 
          AT.7.3    Bit Addressable Registers:  Specific           AT-19 
          AT.7.4    Optional Symbols:  Control Bits                AT-20 
          AT.8    DS80C390 SPECIAL FUNCTION REGISTERS              AT-21 
          AT.8.1    SFR Map                                        AT-21 
          AT.8.2    Bit Addressable Registers:  Generic            AT-22 
          AT.8.3    Bit Addressable Registers:  Specific           AT-23 
          AT.8.4    Optional Symbols:  Control Bits                AT-24 
          AT.9    DS83C520/DS87C520 SPECIAL FUNCTION REGISTERS     AT-26 
          AT.9.1    SFR Map                                        AT-26 
          AT.9.2    Bit Addressable Registers:  Generic            AT-27 
          AT.9.3    Bit Addressable Registers:  Specific           AT-28 
          AT.9.4    Optional Symbols:  Control Bits                AT-29 
          AT.10   DS83C530/DS87C530 SPECIAL FUNCTION REGISTERS     AT-30 
          AT.10.1   SFR Map                                        AT-30 
          AT.10.2   Bit Addressable Registers:  Generic            AT-31 
          AT.10.3   Bit Addressable Registers:  Specific           AT-32 
          AT.10.4   Optional Symbols:  Control Bits                AT-33 
          AT.11   DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS     AT-34 
          AT.11.1   SFR Map                                        AT-34 
          AT.11.2   Bit Addressable Registers:  Generic            AT-36 
          AT.11.3   Bit Addressable Registers:  Specific           AT-37 
          AT.11.4   Optional Symbols:  Control Bits                AT-39 


                                                                 Page xi
        


        APPENDIX AY  ASGB ASSEMBLER                                 AY-1 
          AY.1    ACKNOWLEDGEMENT                                   AY-1 
          AY.2    INTRODUCTION                                      AY-1 
          AY.3    GAMEBOY REGISTER SET AND CONDITIONS               AY-1 
          AY.4    GAMEBOY INSTRUCTION SET                           AY-2 
          AY.4.1    .tile Directive                                 AY-2 
          AY.4.2    Potentially Controversial Mnemonic Selection    AY-4 
          AY.4.2.1    Auto-Indexing Loads                           AY-4 
          AY.4.2.2    Input and Output Operations                   AY-4 
          AY.4.2.3    The 'stop' Instruction                        AY-5 
          AY.4.3    Inherent Instructions                           AY-5 
          AY.4.4    Implicit Operand Instructions                   AY-5 
          AY.4.5    Load Instructions                               AY-6 
          AY.4.6    Call/Return Instructions                        AY-6 
          AY.4.7    Jump Instructions                               AY-6 
          AY.4.8    Bit Manipulation Instructions                   AY-6 
          AY.4.9    Input and Output Instructions                   AY-7 
          AY.4.10   Register Pair Instructions                      AY-7 

        APPENDIX BC  ASRAB ASSEMBLER                                BC-1 
          BC.1    ACKNOWLEDGMENT                                    BC-1 
          BC.2    PROCESSOR SPECIFIC DIRECTIVES                     BC-1 
          BC.2.1    .r2k Directive                                  BC-2 
          BC.2.2    .hd64 Directive                                 BC-2 
          BC.2.3    .z80 Directive                                  BC-2 
          BC.2.4    The .__.CPU.  Variable                          BC-3 
          BC.3    RABBIT 2000/3000 ADDRESSING AND INSTRUCTIONS      BC-4 
          BC.3.1    Instruction Symbols                             BC-4 
          BC.3.2    Rabbit Instructions                             BC-6 
          BC.4    Z80/HD64180 ADDRESSING AND INSTRUCTIONS           BC-8 
          BC.4.1    Inherent Instructions                           BC-9 
          BC.4.2    Implicit Operand Instructions                   BC-9 
          BC.4.3    Load Instruction                               BC-10 
          BC.4.4    Call/Return Instructions                       BC-10 
          BC.4.5    Jump and Jump to Subroutine Instructions       BC-10 
          BC.4.6    Bit Manipulation Instructions                  BC-11 
          BC.4.7    Interrupt Mode and Reset Instructions          BC-11 
          BC.4.8    Input and Output Instructions                  BC-11 
          BC.4.9    Register Pair Instructions                     BC-11 
          BC.4.10   HD64180 Specific Instructions                  BC-12 


                                                               Page xiii
        


        APPENDIX BI  ASZ80 ASSEMBLER                                BI-1 
          BI.1    .z80 DIRECTIVE                                    BI-1 
          BI.2    .hd64 DIRECTIVE                                   BI-1 
          BI.3    THE .__.CPU.  VARIABLE                            BI-2 
          BI.4    Z80 REGISTER SET AND CONDITIONS                   BI-2 
          BI.5    Z80 INSTRUCTION SET                               BI-3 
          BI.5.1    Inherent Instructions                           BI-4 
          BI.5.2    Implicit Operand Instructions                   BI-4 
          BI.5.3    Load Instruction                                BI-5 
          BI.5.4    Call/Return Instructions                        BI-5 
          BI.5.5    Jump and Jump to Subroutine Instructions        BI-5 
          BI.5.6    Bit Manipulation Instructions                   BI-6 
          BI.5.7    Interrupt Mode and Reset Instructions           BI-6 
          BI.5.8    Input and Output Instructions                   BI-6 
          BI.5.9    Register Pair Instructions                      BI-6 
          BI.5.10   HD64180/Z180 Specific Instructions              BI-7 


                                                                  Page 2
        


         
                                  P R E F A C E





           The  ASxxxx  assemblers  were  written following the style of
        several unfinished cross assemblers found in the Digital  Equip-
        ment  Corporation  Users  Society  (DECUS) distribution of the C
        programming language.  The incomplete DECUS  code  was  provided
        with  no  documentation  as  to  the  input syntax or the output
        format.  I wish to thank the author for inspiring  me  to  begin
        the development of this set of assemblers.  

           The  ASLINK  program was written as a companion to the ASxxxx
        assemblers, its design and implementation was not  derived  from
        any other work.  

           I  would  greatly  appreciate  receiving  the  details of any
        changes, additions, or errors pertaining to these  programs  and
        will  attempt  to  incorporate  any  fixes  or  generally useful
        changes in a future update to these programs.  



                Alan R.  Baldwin 
                Kent State University
                Physics Department 
                Kent, Ohio 44242
                U.S.A.  


                http://shop-pdp.net 
                http://shop-pdp.kent.edu/ 

                baldwin@shop-pdp.net 
                baldwin@shop-pdp.kent.edu 

                baldwin@kent.edu 
                tel:  (330) 672 2531 
                fax:  (330) 672 2959 


                                                                  Page 3
        


         
               E N D   U S E R   L I C E N S E   A G R E E M E N T





           Copyright (C) 1989-2012 Alan R.  Baldwin 

           This  program  is  free  software:   you  can redistribute it
        and/or modify it under the  terms  of  the  GNU  General  Public
        License  as  published  by  the Free Software Foundation, either
        version 3 of the License, or (at your option) any later version. 

           This  program is distributed in the hope that it will be use-
        ful, but WITHOUT ANY WARRANTY;  without even  the  implied  war-
        ranty  of  MERCHANTABILITY  or FITNESS FOR A PARTICULAR PURPOSE.
        See the GNU General Public License for more details.  

           You  should  have  received  a copy of the GNU General Public
        License   along   with    this    program.     If    not,    see
        <http://www.gnu.org/licenses/>.  


                                                                  Page 4
        


         




                             C O N T R I B U T O R S



        Thanks  to Marko Makela for his contribution of the AS6500 cross
        assembler.  

                Marko Makela
                Sillitie 10 A
                01480 Vantaa
                Finland
                Internet: Marko dot Makela at Helsinki dot Fi
                EARN/BitNet: msmakela at finuh




        Thanks  to John Hartman for his contribution of the AS8051 cross
        assembler and updates to the ASxxxx and ASLINK internals.  

                John L. Hartman
                jhartman at compuserve dot com
                noice at noicedebugger dot com




        Thanks  to  G.   Osborn  for  his  contributions  to LKS19.C and
        LKIHX.C.  

                G. Osborn
                gary at s-4 dot com




        Thanks to Ken Hornstein for his contribution of object libraries
        contained in LKLIBR.C.  

                Ken Hornstein
                kenh at cmf dot nrl dot navy dot mil






                                                                  Page 5



        Thanks  to  Bill  McKinnon for his contributions to the AS8XCXXX
        cross assembler for the DS8XCXXX series of microprocessors.  

                Bill McKinnon
                w_mckinnon at conknet dot com




        Thanks  to Roger Ivie for his contribution of the ASGB cross as-
        sembler for the GameBoy.  

                Roger Ivie
                ivie at cc dot usu dot edu




        Thanks  to  Uwe  Steller for his contribution of the AS740 cross
        assembler.  

                Uwe Stellar
                Uwe dot Steller at t-online dot de




        Thanks  to  Shujen Chen for his contribution of the AS1802 cross
        assembler.  

                Shugen Chen
                DeVry University
                Tinley Park IL
                schen at tp dot devry dot edu




        Thanks  to  Edgar Puehringer for his contribution of the AS61860
        cross assembler.  

                Edgar Puehringer
                edgar_pue at yahoo dot com






                                                                  Page 6
        


        Thanks to Ulrich Raich and Razaq Ijoduola for their contribution
        of the ASRAB cross assembler.  

                Ulrich Raich and Razaq Ijoduola
                PS Division
                CERN
                CH-1211 Geneva-23
                Ulrich dot Raich at cern dot ch




        Thanks  to Patrick Head for his contribution of the ASEZ80 cross
        assembler.  

                Patrick Head
                patrick at phead dot net




        Thanks  to  Boisy  G.   Pitre for contributing the .ifeq, .ifne,
        .ifgt, .iflt, .ifle, and .ifge conditional  directives  and  the
        Tandy Color Computer Disk Basic binary output for ASLINK.  

                Boisy G. Pitre
                boisy at boisypitre dot com




        Thanks  to  Mike  McCarty for his contributions to the processor
        cycle count option of the ASxxxx Assemblers.  

                Mike McCarty
                mike dot mccarty at sbcglobal dot net




        Thanks  to  Mengjin Su for his contribution of the PIC18Fxxx Ex-
        tended Instructions.  

                Mengjin Su
                msu at micron dot com






                                                                  Page 7
        


        Thanks  to  Carl  Rash for his contribution of the Visual Studio
        2010 project files.  

                Carl Rash
                crash at triad dot rr dot com


                                                                  Page 8
        


        ASxxxx Cross Assemblers, Version 5.05, August 2012 

        Submitted by Alan R.  Baldwin, 
        Kent State University, Kent, Ohio 

        Operating System:  Linux, Windows, MS-DOS 
        or other supporting ANSI C.  

        Source Langauge:  C 

        Abstract:  

           The  ASxxxx  assemblers are a series of microprocessor assem-
        blers written in the C programming  language.   This  collection
        contains  cross  assemblers  for the 1802, S2650, SC/MP, MPS430,
        61860, 6500,  6800(6802/6808),  6801(6803/HD6303),  6804,  6805,
        68HC(S)08,     6809,    68HC11,    68HC(S)12,    68HC16,    740,
        8048(8041/8022/8021)  8051,  8085(8080),  DS8xCxxx,  AVR,  EZ80,
        F2MC8L/FX,  F8/3870,  GameBoy(Z80),  H8/3xx,  Cypress PSoC(M8C),
        PIC, Rabbit 2000/3000, asst6, asst7, asst8, Z8, and Z80(HD64180)
        series  microprocessors.   Each  assembler has a device specific
        section which includes:  (1) device description, byte order, and
        file  extension  information,  (2)  a table of assembler general
        directives, special directives, assembler  mnemonics  and  asso-
        ciated operation codes, (3) machine specific code for processing
        the device mnemonics, addressing modes, and special directives. 

           The assemblers have a common device independent section which
        handles the details of file input/output, symbol  table  genera-
        tion,  program/data  areas,  expression  analysis, and assembler
        directive processing.  

           The  assemblers  provide  the following features:  (1) alpha-
        betized, formatted symbol table listings, (2) relocatable object
        modules, (3) global symbols for linking object modules, (4) con-
        ditional assembly directives, (5) reusable  local  symbols,  (6)
        include-file  processing,  and  (7)  a  general macro processing
        facility.  

           The  companion program ASLINK is a relocating linker perform-
        ing the following functions:  (1) bind multiple  object  modules
        into  a  single  memory  image,  (2) resolve inter-module symbol
        references,  (3)  resolve  undefined  symbols   from   specified
        librarys of object modules, (4) process absolute, relative, con-
        catenated, and overlay attributes in data and program  sections,
        (5)  perform  byte and word program-counter relative (pc or pcr)
        addressing calculations, (6) define absolute  symbol  values  at
        link  time, (7) define absolute area base address values at link
        time, (8) produce an Intel Hex  record,  Motorola  S  record  or
        Tandy  CoCo  Disk  Basic  output  file, (9) produce a map of the
        linked memory  image,  and  (10)  update  the  ASxxxx  assembler
        listing files with the absolute linked addresses and data.  


                                                                  Page 9



           The  assemblers  and  linker have been tested using Linux and
        DJGPP, Cygwin, Symantec C/C++ V7.2, Borland Turbo C++ 3.0,  Open
        Watcom  V1.9,  VC6,  Visual Studio 2005, and Visual Studio 2010.
        Complete source code and documentation for  the  assemblers  and
        linker  is  included  with the distribution.  Additionally, test
        code for each assembler and several  microprocessor  monitors  (
        ASSIST05  for  the  6805,  MONDEB and ASSIST09 for the 6809, and
        BUFFALO 2.5 for the 6811) are included as  working  examples  of
        use of these assemblers.  














                                    CHAPTER 1

                                  THE ASSEMBLER





        1.1  THE ASXXXX ASSEMBLERS


           The  ASxxxx  assemblers are a series of microprocessor assem-
        blers written in the C programming language.  Each assembler has
        a device specific section which includes:

             1.  device  description, byte order, and file extension in-
                 formation

             2.  a  table  of  the assembler general directives, special
                 device directives, assembler mnemonics  and  associated
                 operation codes

             3.  machine specific code for processing the device mnemon-
                 ics, addressing modes, and special directives

        The device specific information is detailed in the appendices.

           The assemblers have a common device independent section which
        handles the details of file input/output, symbol  table  genera-
        tion,  program/data  areas,  expression  analysis, and assembler
        directive processing.

        The assemblers provide the following features:

             1.  Command string control of assembly functions

             2.  Alphabetized, formatted symbol table listing

             3.  Relocatable object modules

             4.  Global symbols for linking object modules

             5.  Conditional assembly directives



        THE ASSEMBLER                                           PAGE 1-2
        THE ASXXXX ASSEMBLERS


             6.  Program sectioning directives


           ASxxxx assembles one or more source files into a single relo-
        catable ascii object file.  The output of the ASxxxx  assemblers
        consists of an ascii relocatable object file(*.rel), an assembly
        listing file(*.lst), and a symbol file(*.sym).


        1.1.1  Assembly Pass 1


           During  pass  1, ASxxxx opens all source files and performs a
        rudimentary assembly of each source statement.  During this pro-
        cess  all symbol tables are built, program sections defined, and
        number of bytes for each assembled source line is estimated.

           At the end of pass 1 all undefined symbols may be made global
        (external) using the ASxxxx switch -g, otherwise undefined  sym-
        bols will be flagged as errors during succeeding passes.


        1.1.2  Assembly Pass 2


           During  pass  2  the ASxxxx assembler resolves forward refer-
        ences and determines the number  of  bytes  for  each  assembled
        line.   The  number  of bytes used by a particular assembler in-
        struction may depend upon the addressing mode, whether  the  in-
        struction allows multiple forms based upon the relative distance
        to the addressed location, or other factors.   Pass  2  resolves
        these cases and determines the address of all symbols.


        1.1.3  Assembly Pass 3


           Pass 3 by the assembler generates the listing file, the relo-
        catable output file, and the symbol tables.  Also during pass  3
        the errors will be reported.

           The  relocatable object file is an ascii file containing sym-
        bol references and definitions, program  area  definitions,  and
        the  relocatable assembled code, the linker ASLINK will use this
        information to generate an absolute load file  (Intel or Motorola
        formats).




        THE ASSEMBLER                                           PAGE 1-3
        SOURCE PROGRAM FORMAT


        1.2  SOURCE PROGRAM FORMAT



        1.2.1  Statement Format


           A source program is composed of assembly-language statements.
        Each statement must be completed on one line.  A line  may  con-
        tain a maximum of 128 characters, longer lines are truncated and
        lost.

           An  ASxxxx  assembler  statement  may  have  as  many as four
        fields.  These fields are identified by their order  within  the
        statement  and/or  by separating characters between fields.  The
        general format of the ASxxxx statement is:

              [label:]  Operator        Operand         [;Comment(s)]

           The  label and comment fields are optional.  The operator and
        operand fields are interdependent.  The operator field may be an
        assembler  directive or an assembly mnemonic.  The operand field
        may be optional or required as defined in  the  context  of  the
        operator.

           ASxxxx  interprets  and  processes source statements one at a
        time.  Each statement causes a particular operation to  be  per-
        formed.


        1.2.1.1  Label Field  -

           A  label is a user-defined symbol which is assigned the value
        of the current location counter and entered into  the  user  de-
        fined  symbol  table.   The  current location counter is used by
        ASxxxx to assign memory addresses to the source  program  state-
        ments as they are encountered during the assembly process.  Thus
        a label is a means  of  symbolically  referring  to  a  specific
        statement.

           When  a program section is absolute, the value of the current
        location counter is absolute;  its value references an  absolute
        memory  address.   Similarly, when a program section is relocat-
        able, the value of the current location counter is  relocatable.
        A  relocation  bias  calculated at link time is added to the ap-
        parent value of the current location counter  to  establish  its
        effective  absolute  address  at  execution time.  (The user can
        also force the linker to relocate sections defined as  absolute.
        This may be required under special circumstances.)

           If  present,  a  label  must  be  the first field in a source
        statement and must be terminated by a colon (:).   For  example,


        THE ASSEMBLER                                           PAGE 1-4
        SOURCE PROGRAM FORMAT


        if  the  value  of  the  current  location  counter  is absolute
        01F0(H), the statement:

              abcd:     nop

        assigns  the  value  01F0(H) to the label abcd.  If the location
        counter value were relocatable, the final value of abcd would be
        01F0(H)+K, where K represents the relocation bias of the program
        section, as calculated by the linker at link time.

           More  than  one label may appear within a single label field.
        Each label so specified is assigned the same address value.  For
        example,  if  the  value  of  the  current  location  counter is
        1FF0(H), the multiple labels in the following statement are each
        assigned the value 1FF0(H):

              abcd:     aq:     $abc:   nop

           Multiple labels may also appear on successive lines.  For ex-
        ample, the statements

              abcd:
              aq:
              $abc:     nop

        likewise  cause  the  same value to be assigned to all three la-
        bels.

           A  double  colon  (::)  defines the label as a global symbol.
        For example, the statement

              abcd::    nop

        establishes the label abcd as a global symbol.  The distinguish-
        ing attribute of a global symbol is that it  can  be  referenced
        from  within an object module other than the module in which the
        symbol is defined.  References to this label  in  other  modules
        are  resolved when the modules are linked as a composite execut-
        able image.

        The legal characters for defining labels are:

                A through Z
                a through z
                0 through 9
                . (Period)
                $ (Dollar sign)
                _ (underscore)

           A  label  may  be  any  length,  however  only  the  first 79
        characters are significant and, therefore must be  unique  among
        all   labels  in  the  source  program  (not  necessarily  among


        THE ASSEMBLER                                           PAGE 1-5
        SOURCE PROGRAM FORMAT


        separately compiled modules).  An error code(s) (m or p) will be
        generated  in the assembly listing if the first 79 characters in
        two or more labels are the same.  The m code is  caused  by  the
        redeclaration  of  the symbol or its reference by another state-
        ment.  The p code is generated because the symbols  location  is
        changing on each pass through the source file.

           The  label  must  not  start with the characters 0-9, as this
        designates a reusable symbol with special  attributes  described
        in a later section.  

           The  label  must  not  start  with  the  sequence $$, as this
        represents the temporary radix 16 for constants.


        1.2.1.2  Operator Field  -

           The  operator field specifies the action to be performed.  It
        may consist of an instruction mnemonic (op code) or an assembler
        directive.

           When  the  operator is an instruction mnemonic, a machine in-
        struction is generated and the assembler evaluates the addresses
        of  the operands which follow.  When the operator is a directive
        ASxxxx performs certain control actions or processing operations
        during assembly of the source program.

           Leading  and  trailing  spaces  or tabs in the operator field
        have no significance;  such characters serve  only  to  separate
        the operator field from the preceeding and following fields.

           An operator is terminated by a space, tab or end of line.


        1.2.1.3  Operand Field  -

           When  the  operator is an instruction mnemonic (op code), the
        operand  field  contains  program  variables  that  are  to   be
        evaluated/manipulated by the operator.

           Operands  may  be  expressions  or  symbols, depending on the
        operator.  Multiple expressions used in the operand  fields  may
        be  separated  by a comma.  An operand should be preceeded by an
        operator field;  if it is not, the statement will give an  error
        (q  or  o).   All  operands  following instruction mnemonics are
        treated as expressions.

           The operand field is terminated by a semicolon when the field
        is followed  by  a  comment.   For  example,  in  the  following
        statement:

              label:    lda     abcd,x          ;Comment field


        THE ASSEMBLER                                           PAGE 1-6
        SOURCE PROGRAM FORMAT



        the  tab  between lda and abcd terminates the operator field and
        defines the beginning of the operand field;  a  comma  separates
        the operands abcd and x;  and a semicolon terminates the operand
        field and defines the beginning of the comment field.   When  no
        comment  field  follows,  the operand field is terminated by the
        end of the source line.


        1.2.1.4  Comment Field  -

           The comment field begins with a semicolon and extends through
        the end of the line.  This field is optional and may contain any
        7-bit ascii character except null.

           Comments  do not affect assembly processing or program execu-
        tion.


        1.3  SYMBOLS AND EXPRESSIONS


           This  section  describes the generic components of the ASxxxx
        assemblers:  the character set, the conventions observed in con-
        structing  symbols,  and  the use of numbers, operators, and ex-
        pressions.


        1.3.1  Character Set


           The following characters are legal in ASxxxx source programs:

             1.  The  letters  A  through Z.  Both upper- and lower-case
                 letters are acceptable.  The  assemblers,  by  default,
                 are  case  sensitive,  i.e.   ABCD and abcd are not the
                 same symbols.  (The assemblers can be made case  insen-
                 sitive by using the -z command line option.) 

             2.  The digits 0 through 9

             3.  The  characters . (period), $ (dollar sign), and _ (un-
                 derscore).

             4.  The special characters listed in Tables 1 through 6.


           Tables  1  through  6  describe  the various ASxxxx label and
        field terminators, assignment operators, operand separators, as-
        sembly, unary, binary, and radix operators.


        THE ASSEMBLER                                           PAGE 1-7
        SYMBOLS AND EXPRESSIONS


        Table 1         Label Terminators and Assignment Operators
        ----------------------------------------------------------------

                :   Colon               Label terminator.

                ::  Double colon        Label  Terminator;   defines the
                                        label as a global label.

                =   Equal sign          Direct assignment operator.

                ==  Global equal        Direct assignment operator;  de-
                                        fines the  symbol  as  a  global
                                        symbol.

                =:  Local equal         Direct assignment operator;  de-
                                        fines the symbol as a local sym-
                                        bol.  

        ----------------------------------------------------------------





        Table 2         Field Terminators and Operand Separators
        ----------------------------------------------------------------

                    Tab                 Item or field terminator.

                    Space               Item or field terminator.

                ,   Comma               Operand field separator.

                ;   Semicolon           Comment field indicator.

        ----------------------------------------------------------------







        THE ASSEMBLER                                           PAGE 1-8
        SYMBOLS AND EXPRESSIONS


        Table 3         Assembler Operators
        ----------------------------------------------------------------

                #   Number sign         Immediate expression indicator.

                .   Period              Current location counter.

                (   Left parenthesis    Expression delimiter.

                )   Right parenthesis   Expression delimeter.

        ----------------------------------------------------------------





        Table 4         Unary Operators
        ----------------------------------------------------------------

                <   Left bracket        <FEDC   Produces  the lower byte
                                                value of the expression.
                                                (DC)

                >   Right bracket       >FEDC   Produces  the upper byte
                                                value of the expression.
                                                (FE)

                +   Plus sign           +A      Positive value of A

                -   Minus sign          -A      Produces   the  negative
                                                (2's complement) of A.

                ~   Tilde               ~A      Produces the 1's comple-
                                                ment of A.

                '   Single quote        'D      Produces  the  value  of
                                                the character D.

                "   Double quote        "AB     Produces the double byte
                                                value for AB.

                \   Backslash           '\n     Unix style characters
                                                \b, \f, \n, \r, \t
                                     or '\001   or octal byte values.

        ----------------------------------------------------------------







        THE ASSEMBLER                                           PAGE 1-9
        SYMBOLS AND EXPRESSIONS


        Table 5         Binary Operators
        ----------------------------------------------------------------

                <<  Double          0800 << 4   Produces the 4 bit
                    Left bracket                left-shifted   value  of
                                                0800.  (8000)

                >>  Double          0800 >> 4   Produces the 4 bit
                    Right bracket               right-shifted  value  of
                                                0800.  (0080)

                +   Plus sign       A + B       Arithmetic      Addition
                                                operator.

                -   Minus sign      A - B       Arithmetic   Subtraction
                                                operator.

                *   Asterisk        A * B       Arithmetic   Multiplica-
                                                tion operator.  

                /   Slash           A / B       Arithmetic      Division
                                                operator.  

                &   Ampersand       A & B       Logical AND operator.

                |   Bar             A | B       Logical OR operator.

                %   Percent sign    A % B       Modulus operator.

                ^   Up arrow or     A ^ B       EXCLUSIVE OR operator.
                    circumflex

        ----------------------------------------------------------------





        Table 6         Temporary Radix Operators
        ----------------------------------------------------------------

                $%,   0b, 0B            Binary radix operator.

                $&,   0o, 0O, 0q, 0Q    Octal radix operator.

                $#,   0d, 0D            Decimal radix operator.

                $$,   0h, 0H, 0x, 0X    Hexadecimal radix operator.


                Potential  ambiguities arising from the use of 0b and 0d
                as temporary radix  operators  may  be  circumvented  by


        THE ASSEMBLER                                          PAGE 1-10
        SYMBOLS AND EXPRESSIONS


                preceding  all non-prefixed hexadecimal numbers with 00.
                Leading 0's are required in any  case  where  the  first
                hexadecimal  digit is abcdef as the assembler will treat
                the letter sequence as a label.

        ----------------------------------------------------------------







        1.3.2  User-Defined Symbols


           User-defined  symbols are those symbols that are equated to a
        specific value through a direct assignment statement  or  appear
        as  labels.  These symbols are added to the User Symbol Table as
        they are encountered during assembly.

        The following rules govern the creation of user-defined symbols:

             1.  Symbols  can  be  composed  of alphanumeric characters,
                 dollar signs ($),  periods  (.),  and  underscores  (_)
                 only.

             2.  The  first  character  of a symbol must not be a number
                 (except in the case of reusable symbols).  

             3.  The  first 79 characters of a symbol must be unique.  A
                 symbol  can  be  written  with  more  than   79   legal
                 characters,  but the 80th and subsequent characters are
                 ignored.

             4.  Spaces and Tabs must not be embedded within a symbol.



        1.3.3  Reusable Symbols 


           Reusable  symbols are specially formatted symbols used as la-
        bels within a block of coding that has been delimited as a reus-
        able symbol block.  Reusable symbols are of the form n$, where n
        is a decimal integer from 0 to 65535,  inclusive.   Examples  of
        reusable symbols are:  

              1$
              27$
              138$
              244$


        THE ASSEMBLER                                          PAGE 1-11
        SYMBOLS AND EXPRESSIONS


           The range of a reusable symbol block consists of those state-
        ments between two normally constructed  symbolic  labels.   Note
        that a statement of the form:

              ALPHA = EXPRESSION

        is a direct assignment statement but does not create a label and
        thus does not delimit the range of a reusable symbol block.  

           Note  that  the  range  of a reusable symbol block may extend
        across program areas.  

           Reusable symbols provide a convenient means of generating la-
        bels for branch instructions and other  such  references  within
        reusable symbol blocks.  Using reusable symbols reduces the pos-
        sibility of symbols with multiple definitions appearing within a
        user  program.   In  addition,  the use of reusable symbols dif-
        ferentiates entry-point labels from other labels, since reusable
        labels cannot be referenced from outside their respective symbol
        blocks.  Thus, reusable symbols of the same name can  appear  in
        other  symbol blocks without conflict.  Reusable symbols require
        less symbol table space  than  normal  symbols.   Their  use  is
        recommended.  

           The  use  of  the  same reusable symbol within a symbol block
        will generate one or both of the m or p errors.

        Example of reusable symbols:  

                a:      ldx     #atable ;get table address
                        lda     #0d48   ;table length
                1$:     clr     ,x+     ;clear
                        deca
                        bne     1$

                b:      ldx     #btable ;get table address
                        lda     #0d48   ;table length
                1$:     clr     ,x+     ;clear
                        deca
                        bne     1$




        THE ASSEMBLER                                          PAGE 1-12
        SYMBOLS AND EXPRESSIONS


        1.3.4  Current Location Counter


           The  period  (.) is the symbol for the current location coun-
        ter.  When used in the operand  field  of  an  instruction,  the
        period   represents  the  address  of  the  first  byte  of  the
        instruction:

                AS:     ldx     #.      ;The period (.) refers to
                                        ;the address of the ldx
                                        ;instruction.

           When  used  in  the  operand field of an ASxxxx directive, it
        represents the address of the current byte or word:

                QK = 0

                .word   0xFFFE,.+4,QK   ;The operand .+4 in the .word
                                        ;directive represents a value
                                        ;stored in the second of the
                                        ;three words during assembly.

           If  we  assume  the  current  value of the program counter is
        0H0200, then during assembly, ASxxxx  reserves  three  words  of
        storage  starting  at  location 0H0200.  The first value, a hex-
        idecimal constant FFFE, will be stored at location 0H0200.   The
        second  value  represented  by  .+4  will  be stored at location
        0H0202, its value will be 0H0206 ( = 0H0202  +  4).   The  third
        value  defined  by  the  symbol  QK  will  be placed at location
        0H0204.

           At the beginning of each assembly pass, ASxxxx resets the lo-
        cation counter.  Normally, consecutive memory locations are  as-
        signed  to  each  byte  of  object code generated.  However, the
        value of the location counter can be changed  through  a  direct
        assignment statement of the following form:

              . = . + expression


           The  new  location  counter can only be specified relative to
        the current location counter.  Neglecting to specify the current
        program  counter  along with the expression on the right side of
        the assignment operator will generate the (.) error.   (Absolute
        program areas may use the .org directive to specify the absolute
        location of the current program counter.)

        The following coding illustrates the use of the current location
        counter:

                .area   CODE1   (ABS)   ;program area CODE1
                                        ;is ABSOLUTE


        THE ASSEMBLER                                          PAGE 1-13
        SYMBOLS AND EXPRESSIONS



                .org    0H100           ;set location to
                                        ;0H100 absolute

        num1:   ldx     #.+0H10         ;The label num1 has
                                        ;the value 0H100.
                                        ;X is loaded with
                                        ;0H100 + 0H10

                .org    0H130           ;location counter
                                        ;set to 0H130

        num2:   ldy     #.              ;The label num2 has
                                        ;the value 0H130.
                                        ;Y is loaded with
                                        ;value 0H130.


                .area   CODE2   (REL)   ;program area CODE2
                                        ;is RELOCATABLE

                . = . + 0H20            ;Set location counter
                                        ;to relocatable 0H20 of
                                        ;the program section.

        num3:   .word   0               ;The label num3 has
                                        ;the value
                                        ;of relocatable 0H20.

                . = . + 0H40            ;will reserve 0H40
                                        ;bytes of storage as will
                .blkb   0H40            ;or
                .blkw   0H20

           The  .blkb  and .blkw directives are the preferred methods of
        allocating space.


        1.3.5  Numbers


           ASxxxx  assumes that all numbers in the source program are to
        be interpreted in decimal radix unless otherwise specified.  The
        .radix  directive  may  be used to specify the default as octal,
        decimal, or hexadecimal.  Individual numbers can  be  designated
        as  binary, octal, decimal, or hexadecimal through the temporary
        radix prefixes shown in table 6.

           Negative  numbers  must be preceeded by a minus sign;  ASxxxx
        translates such numbers into two's  complement  form.   Positive
        numbers may (but need not) be preceeded by a plus sign.



        THE ASSEMBLER                                          PAGE 1-14
        SYMBOLS AND EXPRESSIONS


           Numbers are always considered to be absolute values, therefor
        they are never relocatable.


        1.3.6  Terms


           A  term is a component of an expression and may be one of the
        following:


             1.  A number.

             2.  A symbol:
                 1.  A  period (.) specified in an expression causes the
                     current location counter to be used.
                 2.  A User-defined symbol.
                 3.  An undefined symbol is assigned a value of zero and
                     inserted in the User-Defined symbol table as an un-
                     defined symbol.

             3.  A single quote followed by a single ascii character, or
                 a double quote followed by two ascii characters.

             4.  An  expression enclosed in parenthesis.  Any expression
                 so enclosed is evaluated and reduced to a  single  term
                 before  the remainder of the expression in which it ap-
                 pears is evaluated.  Parenthesis, for example,  may  be
                 used  to  alter the left-to-right evaluation of expres-
                 sions, (as in A*B+C versus A*(B+C)), or to apply a  un-
                 ary operator to an entire expression (as in -(A+B)).

             5.  A unary operator followed by a symbol or number.



        1.3.7  Expressions 


           Expressions  are  combinations  of  terms  joined together by
        binary operators.  Expressions reduce to a value.   The  evalua-
        tion  of  an expression includes the determination of its attri-
        butes.  A resultant expression value may be one of  three  types
        (as  described  later  in this section):  relocatable, absolute,
        and external.  



        THE ASSEMBLER                                          PAGE 1-15
        SYMBOLS AND EXPRESSIONS


        Expressions are evaluate with an operand hierarchy as follows:

                *       /       %       multiplication,
                                        division, and
                                        modulus first.

                +       -               addition and
                                        subtraction second.

                <<      >>              left shift and
                                        right shift third.

                ^                       exclusive or fourth.

                &                       logical and fifth.

                |                       logical or last

                except that unary operators take precedence over binary
                operators.


           A  missing  or  illegal  operator  terminates  the expression
        analysis, causing error codes (o) and/or  (q)  to  be  generated
        depending upon the context of the expression itself.

           At assembly time the value of an external (global) expression
        is equal to the value of the absolute part of  that  expression.
        For  example,  the expression external+4, where 'external' is an
        external symbol, has the value of 4.  This expression,  however,
        when  evaluated  at link time takes on the resolved value of the
        symbol 'external', plus 4.

           Expressions,  when  evaluated  by  ASxxxx,  are  one of three
        types:  relocatable, absolute, or external.  The following  dis-
        tinctions are important:

             1.  An  expression is relocatable if its value is fixed re-
                 lative to the base address of the program area in which
                 it appears;  it will have an offset value added at link
                 time.  Terms that contain labels defined in relocatable
                 program  areas  will  have  a relocatable value;  simi-
                 larly, a period (.)  in  a  relocatable  program  area,
                 representing  the value of the current program location
                 counter, will also have a relocatable value.

             2.  An  expression  is  absolute if its value is fixed.  An
                 expression whose terms are numbers and ascii characters
                 will  reduce  to  an absolute value.  A relocatable ex-
                 pression or term minus a relocatable term,  where  both
                 elements  being  evaluated  belong  to the same program
                 area, is an absolute expression.  This is because every


        THE ASSEMBLER                                          PAGE 1-16
        SYMBOLS AND EXPRESSIONS


                 term  in  a  program area has the same relocation bias.
                 When one term is subtracted from the other the  reloca-
                 tion bias is zero.

             3.  An  expression is external (or global) if it contains a
                 single global reference (plus or minus an absolute  ex-
                 pression  value) that is not defined within the current
                 program.  Thus, an external  expression  is  only  par-
                 tially  defined following assembly and must be resolved
                 at link time.



        1.4  GENERAL ASSEMBLER DIRECTIVES


           An  ASxxxx  directive  is placed in the operator field of the
        source line.  Only one directive is  allowed  per  source  line.
        Each  directive  may  have  a blank operand field or one or more
        operands.  Legal operands differ with each directive.


        1.4.1  .module Directive

        Format:

                .module name 

           The  .module  directive causes the name to be included in the
        assemblers output file as an identifier for this particular  ob-
        ject module.  The name may be from 1 to 79 characters in length.
        The name may not have any embedded white space (spaces or tabs).
        Only  one  identifier is allowed per assembled module.  The main
        use of this directive  is  to  allow  the  linker  to  report  a
        modules'  use  of undefined symbols.  At link time all undefined
        symbols  are  reported  and  the  modules  referencing  them are
        listed.


        1.4.2  .title Directive

        Format:

                .title  string

           The .title directive provides a character string to be placed
        on the second line of each page during listing.  The string  be-
        gins  with  the first non white space character (after any space
        or tab) and ends with the end of the line.  




        THE ASSEMBLER                                          PAGE 1-17
        GENERAL ASSEMBLER DIRECTIVES


        1.4.3  .sbttl Directive

        Format:

                .sbttl  string

           The .sbttl directive provides a character string to be placed
        on the third line of each page during listing.  The  string  be-
        gins  with  the first non white space character (after any space
        or tab) and ends with the end of the line.  


        1.4.4  .list and .nlist Directives 

        Format:  

                .list                           ;Basic .list 

                .list   expr                    ;with expression 

                .list   (arg1,arg2,...,argn)    ;with sublist options 

                .nlist                          ;Basic .nlist 

                .nlist  expr                    ;with expression 

                .nlist  (arg1,arg2,...,argn)    ;with sublist options 


        The  .list  and  .nlist directives control the listing output to
        the .lst  file.   The  directives  have  the  following  sublist
        options:  

                err     -       errors
                loc     -       program location
                bin     -       binary output
                eqt     -       symbol or .if evaluation
                cyc     -       opcode cycle count
                lin     -       source line number
                src     -       source line text
                pag     -       pagination
                lst     -       .list/.nlist line listing
                md      -       macro definition listing
                me      -       macro expansion listing
                meb     -       macro expansion binary listing

                !       -       sets the listing mode to
                                !(.list) or !(.nlist) before
                                applying the sublist options


        The  'normal' listing mode .list is the combination of err, loc,


        THE ASSEMBLER                                          PAGE 1-18
        GENERAL ASSEMBLER DIRECTIVES


        bin, eqt, cyc, lin, src, pag, lst, and md enabled  with  me  and
        meb  disabled.  The 'normal' listing mode .nlist has all sublist
        items disabled.  When specifying sublist options the option list
        must   be  enclosed  within  parenthesis  and  multiple  options
        seperated by commas.  

           The NOT option, !, is used to set the listing mode to the op-
        posite of the .list or .nlist directive before applying the sub-
        list options.  For example:  

                .nlist  (!)     is equivalent to .list  and
                .list   (!)     is equivalent to .nlist
                                any additional options will
                                be applied normally


           Normal  .list/.nlist processing is disabled within false con-
        ditional blocks.  However, the .list/.nlist with  an  expression
        can  override  this  behavior  if  the expression has a non zero
        value.  

           Examples of listing options:  

                .list   (meb)   ; lists macro generated binary
        
                .list   (me)    ; lists macro expansions

                .nlist  (src)   ; .nlist src lines not listed
        
                .nlist  (!,lst) ; list all except .nlist
        
                .nlist          ; combination lists only
                .list   (src)   ; the source line
        
                .list   (!,src) ; list only the source line
        
                .list   1       ; enable listing even within
                                ; a FALSE conditional block


        1.4.5  .page Directive 

        Format:

                .page

           The .page directive causes a page ejection with a new heading
        to be printed.  The new page occurs after the next line  of  the
        source  program is processed, this allows an immediately follow-
        ing .sbttl directive to appear  on  the  new  page.   The  .page
        source  line will not appear in the file listing.  Paging may be
        disabled by invoking the -p directive or by using the directive: 


        THE ASSEMBLER                                          PAGE 1-19
        GENERAL ASSEMBLER DIRECTIVES



                .nlist  (pag)


           If  the .page directive is followed by a non zero constant or
        an expression that evaluates to a non zero value then pagination
        will be enabled within a false condition range to allow extended
        textual information to be incorporated  in  the  source  program
        with out the need to use the comment delimiter (;):  

                .if     0
        
                .page   1       ;Enable pagination within 'if' block.
                This text will be bypassed during assembly
                but appear in the listing file.
                .
                .
                .
        
                .endif





        1.4.8  .byte, .db, and .fcb Directives

        Format:

                .byte   exp             ;Stores the binary value
                .db     exp             ;of the expression in the
                .fcb    exp             ;next byte.

                .byte   exp1,exp2,expn  ;Stores the binary values
                .db     exp1,exp2,expn  ;of the list of expressions
                .fcb    exp1,exp2,expn  ;in successive bytes.

        where:  exp,    represent expressions that will be
                exp1,   truncated to 8-bits of data.
                .       Each expression will be calculated,
                .       the high-order byte will be truncated.
                .       Multiple expressions must be
                expn    separated by commas.

           The  .byte, .db, or .fcb directives are used to generate suc-
        cessive bytes of binary data in the object module.  




        THE ASSEMBLER                                          PAGE 1-21
        GENERAL ASSEMBLER DIRECTIVES


        1.4.9  .word, .dw, and .fdb Directives 

        Format:

                .word   exp             ;Stores the binary value
                .dw     exp             ;of the expression in
                .fdb    exp             ;the next word.

                .word   exp1,exp2,expn  ;Stores the binary values
                .dw     exp1,exp2,expn  ;of the list of expressions
                .fdb    exp1,exp2,expn  ;in successive words.

        where:  exp,    represent expressions that will occupy two
                exp1,   bytes of data. Each expression will be
                .       calculated as a 16-bit word expression.
                .       Multiple expressions must be
                expn    separated by commas.

           The  .word, .dw, or .fdb directives are used to generate suc-
        cessive words of binary data in the object module.  



        THE ASSEMBLER                                          PAGE 1-22
        GENERAL ASSEMBLER DIRECTIVES


        1.4.12  .blkb, .ds, .rmb, and .rs Directives 

        Format:

                .blkb   N       ;reserve N bytes of space
                .ds     N       ;reserve N bytes of space
                .rmb    N       ;reserve N bytes of space
                .rs     N       ;reserve N bytes of space

           The  .blkb, .ds, .rmb, and .rs directives reserve byte blocks
        in the object module;  


        1.4.13  .blkw, .blk3, and .blk4 Directives 

        Format:  

                .blkw   N       ;reserve N words of space
                .blk3   N       ;reserve N triples of space
                .blk4   N       ;reserve N quads of space

           The .blkw directive reserves word blocks;  the .blk3 reserves
        3  byte  blocks(available  in   assemblers   supporting   24-bit
        addressing);  the .blk4 reserves 4 byte blocks (available in as-
        semblers supporting 32-bit addressing).  




        THE ASSEMBLER                                          PAGE 1-23
        GENERAL ASSEMBLER DIRECTIVES


        1.4.14  .ascii, .str, and .fcc Directives 

        Format:

                .ascii   /string/               or 

                .ascii  ^/string/ 

                .fcc     /string/               or 

                .fcc    ^/string/ 

                .str     /string/               or 

                .str    ^/string/ 


        where:  string  is a string of printable ascii characters.

                /  /    represent   the  delimiting  characters.   These
                        delimiters   may   be   any   paired    printing
                        characters,  as  long  as the characters are not
                        contained within  the  string  itself.   If  the
                        delimiting  characters  do not match, the .ascii
                        directive will give the (q) error.

        The  .ascii,  .fcc, and .str directives place one binary byte of
        data for each character in the string into the object module.  


        1.4.15  .ascis and .strs Directives 

        Format:

                .ascis   /string/               or 

                .ascis  ^/string/ 

                .strs    /string/               or 

                .strs   ^/string/ 


        where:  string  is a string of printable ascii characters.

                /  /    represent   the  delimiting  characters.   These
                        delimiters   may   be   any   paired    printing
                        characters,  as  long  as the characters are not
                        contained within  the  string  itself.   If  the
                        delimiting  characters  do not match, the .ascis
                        and .strs directives will give the (q) error.  



        THE ASSEMBLER                                          PAGE 1-24
        GENERAL ASSEMBLER DIRECTIVES


           The .ascis and .strs directives place one binary byte of data
        for each character in the string into the  object  module.   The
        last character in the string will have the high order bit set.  


        1.4.16  .asciz and .strz Directives 

        Format:

                .asciz   /string/               or 

                .asciz  ^/string/ 

                .strz    /string/               or 

                .strz   ^/string/ 


        where:  string  is a string of printable ascii characters.

                /  /    represent   the  delimiting  characters.   These
                        delimiters   may   be   any   paired    printing
                        characters,  as  long  as the characters are not
                        contained within  the  string  itself.   If  the
                        delimiting  characters  do not match, the .asciz
                        and .strz directive will give the (q) error.  


           The .asciz and .strz directives place one binary byte of data
        for each character in the string into the object  module.   Fol-
        lowing  all  the  character data a zero byte is inserted to ter-
        minate the character string.  


        THE ASSEMBLER                                          PAGE 1-25
        GENERAL ASSEMBLER DIRECTIVES


        1.4.18  .radix Directive 

        Format:

                .radix  character

        where:  character  represents  a single character specifying the
                default radix to be used for  succeeding  numbers.   The
                character may be any one of the following:  

                        B,b     Binary

                        O,o     Octal
                        Q,q

                        D,d     Decimal
                        'blank'

                        H,h     Hexadecimal
                        X,x


        1.4.19  .even Directive 

        Format:

                .even

           The .even directive ensures that the current location counter
        contains an even boundary value by adding 1 if the current loca-
        tion is odd.


        1.4.20  .odd Directive 

        Format:

                .odd

           The  .odd directive ensures that the current location counter
        contains an odd boundary value by adding one if the current  lo-
        cation is even.




        THE ASSEMBLER                                          PAGE 1-26
        GENERAL ASSEMBLER DIRECTIVES


        1.4.21  .bndry Directive 

        Format:  

                .bndry  n 

           If  the current location is not an integer multiple of n then
        the location counter is increased to the next  integer  multiple
        of n.  

           As an example:  

                .bndry  4 

        changes  the current location to be at a multiple of 4, a 4-byte
        boundary.  

           The  relocation  and/or  concatenation  of an area containing
        .bndry directives to place code at specific boundaries will  NOT
        maintain  the  specified  boundaries.  When relocating such code
        areas you must specify the base addresses to the linker manually
        and/or  you must pad the allocated space of an area to match the
        boundary conditions.  

           As  an  example  suppose  you wish to link multiple assembled
        code sections, each of which has code for the same area and  re-
        quires a 4 byte boundary.  The starting address of the area must
        be specified to the linker on a 4 byte  boundary  and  each  as-
        sembled code section must be padded to fill out the area in each
        of the individually assembled files.  The  following  code  will
        provide  the necessary area padding to allow a succesful linking
        of files and maintain the boundary requirements:  

                .$.end = .              ; end of area address
                .bndry  4               ; set boundary
                .if ne,. - .$.end       ; is . the same ?
                  . = . - 1             ; no: backup 1 byte
                  .byte 0               ; place padding byte
                .endif


           If  all  files  are  assembled  simultaneously  then only the
        .bndry directive is required at the beginning  of  the  area  in
        each  file and the initial area address must be specified to the
        linker.  




        THE ASSEMBLER                                          PAGE 1-27
        GENERAL ASSEMBLER DIRECTIVES


        1.4.22  .area Directive 

        Format:

                .area   name    [(options)]

        where:  name    represents the symbolic name of the program sec-
                        tion.   This  name  may  be  the  same  as   any
                        user-defined  symbol  as  the area names
                        are independent of all symbols and labels.

                options specify the type of program or data area:
                        ABS     absolute (automatically invokes OVR)
                        REL     relocatable
                        OVR     overlay
                        CON     concatenate
                        NOPAG   non-paged area 
                        PAG     paged area


           The .area directive provides a means of defining and separat-
        ing multiple programming and data sections.   The  name  is  the
        area  label used by the assembler and the linker to collect code
        from various separately assembled modules into one section.  The
        name may be from 1 to 79 characters in length.  

           The options are specified within parenthesis and separated by
        commas as shown in the following example:

                .area  TEST  (REL,CON)  ;This section is relocatable
                                        ;and concatenated with other
                                        ;sections of this program area.

                .area  DATA  (REL,OVR)  ;This section is relocatable
                                        ;and overlays other sections
                                        ;of this program area.

                .area  SYS   (ABS,OVR)  ;(CON not allowed with ABS)
                                        ;This section is defined as
                                        ;absolute. Absolute sections
                                        ;are always overlayed with
                                        ;other sections of this program
                                        ;area.



        THE ASSEMBLER                                          PAGE 1-28
        GENERAL ASSEMBLER DIRECTIVES


                .area  PAGE  (PAG)      ;This is a paged section. The
                                        ;section must be on a 256 byte
                                        ;boundary and its length is
                                        ;checked by the linker to be
                                        ;no larger than 256 bytes.
                                        ;This is useful for direct page
                                        ;areas.

           The  default  area type is REL|CON;  i.e.  a relocatable sec-
        tion which is concatenated with other sections of code with  the
        same area name.  The ABS option indicates an absolute area.  The
        OVR and CON options indicate if program  sections  of  the  same
        name  will overlay each other (start at the same location) or be
        concatenated with each other (appended to each other).

           Multiple  invocations  of  the  .area directive with the same
        name must specify the same options or leave  the  options  field
        blank,  this  defaults  to  the previously specified options for
        this program area.



        THE ASSEMBLER                                          PAGE 1-29
        GENERAL ASSEMBLER DIRECTIVES


        The   ASxxxx   assemblers   automatically  provide  two  program
        sections:


                '_CODE'         This  is  the default code/data area.
                                This program area is of type (REL,CON).
        The  ASxxxx  assemblers  also automatically generate two symbols
        for each program area:

                's_<area>'      This is the starting address of the pro-
                                gram area.

                'l_<area>'      This is the length of the program area.

        The .area names and options are never case sensitive.  


        1.4.24  .org Directive 

        Format:

                .org    exp

        where:  exp     is  an absolute expression that becomes the cur-
                        rent location counter.

        The  .org directive is valid only in an absolute program section
        and will give a (q) error if used in a relocatable program area.
        The  .org  directive specifies that the current location counter
        is to become the specified absolute value.




        THE ASSEMBLER                                          PAGE 1-31
        GENERAL ASSEMBLER DIRECTIVES


        1.4.25  .globl Directive 

        Format:

                .globl  sym1,sym2,...,symn

        where:  sym1,           represent legal symbolic names.
                sym2,...        When multiple symbols are specified,
                symn            they are separated by commas.

           A  .globl directive may also have a label field and/or a com-
        ment field.

           The  .globl directive is provided to export (and thus provide
        linkage to) symbols not  otherwise  defined  as  global  symbols
        within  a  module.   In  exporting  global symbols the directive
        .globl J is similar to:

              J == expression or J::

           Because  object  modules  are linked by global symbols, these
        symbols are vital to a program.  All internal symbols  appearing
        within  a  given program must be defined at the end of pass 1 or
        they will be considered undefined.  The assembly directive  (-g)
        can  be  invoked to make all undefined symbols global at the end
        of pass 1.  

           The  .globl directive and == construct can be overridden by a
        following .local directive.  


                                      NOTE

             The  ASxxxx  assemblers  use the last occurring symbol
             specification in the source file(s) as the type  shown
             in the symbol table and output to the .rel file.  




        1.4.26  .local Directive 

        Format:  

                .local  sym1,sym2,...,symn 

        where:  sym1,           represent legal symbolic names.
                sym2,...        When multiple symbols are specified,
                symn            they are separated by commas.

           A  .local directive may also have a label field and/or a com-
        ment field.  


        THE ASSEMBLER                                          PAGE 1-32
        GENERAL ASSEMBLER DIRECTIVES


           The  .local  directive is provided to define symbols that are
        local to the current assembly process.  Local  symbols  are  not
        effected  by  the assembler option -a (make all symbols global).
        In defining local symbols the directive .local J is similar to: 

              J =: expression 

           The  .local directive and the =:  construct are useful in de-
        fining symbols and constants within a header or definition  file
        that contains many symbols specific to the current assembly pro-
        cess that should not be exported into the .rel output  file.   A
        typical  usage  is  in  the definition of SFRs (Special Function
        Registers) for a microprocessor.  

           The .local directive and =:  construct can be overridden by a
        following .globl directive.  


                                      NOTE

             The  ASxxxx  assemblers  use the last occurring symbol
             specification in the source file(s) as the type  shown
             in the symbol table and output to the .rel file.  




        1.4.27  .equ, .gblequ, and .lclequ Directives 

        Format:  

                sym1    .equ    expr    ; equivalent to sym1  = expr
                sym2    .gblequ expr    ; equivalent to sym2 == expr
                sym3    .lclequ expr    ; equivalent to sym3 =: expr
        
                or
        
                .equ    sym1,   expr    ; equivalent to sym1  = expr
                .gblequ sym2,   expr    ; equivalent to sym2 == expr
                .lclequ sym3,   expr    ; equivalent to sym3 =: expr

           These  alternate  forms  of equivalence are provided for user
        convenience.  




        THE ASSEMBLER                                          PAGE 1-33
        GENERAL ASSEMBLER DIRECTIVES


        1.4.28  .if, .else, and .endif Directives 

        Format:

                .if     expr
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the test condition.  

           The  range of true condition will be processed if the expres-
        sion 'expr' is not zero (i.e.  true) and the range of false con-
        dition  will  be processed if the expression 'expr' is zero (i.e
        false).  The range of true condition is optional as is the .else
        directive  and  the range of false condition.  The following are
        all valid .if/.else/.endif constructions:

                .if     A-4             ;evaluate A-4
                .byte   1,2             ;insert bytes if A-4 is
                .endif                  ;not zero

                .if     K+3             ;evaluate K+3
                .else
                .byte   3,4             ;insert bytes if K+3
                .endif                  ;is zero

                .if     J&3             ;evaluate J masked by 3
                .byte   12              ;insert this byte if J&3
                .else                   ;is not zero
                .byte   13              ;insert this byte if J&3
                .endif                  ;is zero


        All .if/.else/.endif directives are limited to a maximum nesting
        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  




        THE ASSEMBLER                                          PAGE 1-34
        GENERAL ASSEMBLER DIRECTIVES


        1.4.29  .iff, .ift, and .iftf Directives 

        Format:  

                .if     expr    ;'if' range Condition is
                                ;TRUE when expr is not zero
                 .ift                                   ;}
                 .      ;} range of true condition      ;}
                 .iff                                   ;} if
                 .      ;} range of false condition     ;} block
                 .iftf                                  ;}
                 .      ;} unconditional range          ;}
                .else           ;'else' range Condition is
                                ;TRUE when expr is zero
                 .ift                                   ;}
                 .      ;} range of true condition      ;}
                 .iff                                   ;} else
                 .      ;} range of false condition     ;} block
                 .iftf                                  ;}
                 .      ;} unconditional range          ;}
                .endif

           The  subconditional  assembly directives may be placed within
        conditional assembly blocks to indicate:  

                1. The assembly of an alternate body of code when
                   the condition of the block tests false.
        
                2. The assembly of non-contiguous body of code
                   within the conditional assembly block,
                   depending upon the result of the conditional
                   test in entering the block.
        
                3. The unconditional assembly of a body of code
                   within a conditional assembly block.


        The use of the .iff, .ift, and .iftf directives makes the use of
        the .else directive redundant.  

           Note  that  the  implementation of the .else directive causes
        the .if tested condition to be complemented.  The TRUE and FALSE
        conditions are determined by the .if/.else conditional state.  

           All  .if/.else/.endif  directives  are  limited  to a maximum
        nesting of 10 levels.  

           The  use  of the .iff, .ift, or .iftf directives outside of a
        conditional block results in a (i) error code.  



        THE ASSEMBLER                                          PAGE 1-35
        GENERAL ASSEMBLER DIRECTIVES


           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.30  .ifxx Directives 


           Additional  conditional  directives are available to test the
        value of an evaluated expression:  

                .ifne   expr            ; true if expr != 0
                .ifeq   expr            ; true if expr == 0
                .ifgt   expr            ; true if expr >  0
                .iflt   expr            ; true if expr <  0
                .ifge   expr            ; true if expr >= 0
                .ifle   expr            ; true if expr <= 0

           Format:  

                .ifxx   expr
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the test condition.  

           The  range of true condition will be processed if the expres-
        sion 'expr' is not zero (i.e.  true) and the range of false con-
        dition  will  be processed if the expression 'expr' is zero (i.e
        false).  The range of true condition is optional as is the .else
        directive  and  the range of false condition.  The following are
        all valid .ifxx/.else/.endif constructions:  

                .ifne   A-4             ;evaluate A-4
                .byte   1,2             ;insert bytes if A-4 is
                .endif                  ;not zero
        
                .ifeq   K+3             ;evaluate K+3
                .byte   3,4             ;insert bytes if K+3
                .endif                  ;is zero
        
                .ifne   J&3             ;evaluate J masked by 3
                .byte   12              ;insert this byte if J&3
                .else                   ;is not zero


        THE ASSEMBLER                                          PAGE 1-36
        GENERAL ASSEMBLER DIRECTIVES


                .byte   13              ;insert this byte if J&3
                .endif                  ;is zero


        All .if/.else/.endif directives are limited to a maximum nesting
        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.31  .ifdef Directive 

        Format:  

                .ifdef  sym
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the test condition.  

           The  range  of true condition will be processed if the symbol
        'sym' has been defined with a .define directive or  'sym'  is  a
        variable  with  an  assigned  value else the false range will be
        processed.  The range of true condition is optional  as  is  the
        .else directive and the range of false condition.  The following
        are all valid .ifdef/.else/.endif constructions:  

                .ifdef  sym$1           ;lookup symbol sym$1
                .byte   1,2             ;insert bytes if sym$1
                .endif                  ;is defined or
                                        ;assigned a value
        
                .ifdef  sym$2           ;lookup symbol sym$2
                .else
                .byte   3,4             ;insert bytes if sym$1
                .endif                  ;is not defined and
                                        ;not assigned a value
        
                .ifdef  sym$3           ;lookup symbol sym$3
                .byte   12              ;insert this byte if sym$3
                .else                   ;is defined/valued
                .byte   13              ;insert this byte if sym$3


        THE ASSEMBLER                                          PAGE 1-37
        GENERAL ASSEMBLER DIRECTIVES


                .endif                  ;is not defined/valued


        Note  that the default assembler configuration of case sensitive
        means the testing for a defined symbol is also case sensitive.  

           All  .if/.else/.endif  directives  are  limited  to a maximum
        nesting of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.32  .ifndef Directive 

        Format:  

                .ifndef sym
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the condition test.  

           The  range  of true condition will be processed if the symbol
        'sym' is not defined by a .define directive and a variable 'sym'
        has  not been assigned a value else the range of false condition
        will be processed.  The range of true condition is  optional  as
        is  the  .else  directive and the range of false condition.  The
        following are all valid .ifndef/.else/.endif constructions:  

                .ifndef sym$1           ;lookup symbol sym$1
                .byte   1,2             ;insert bytes if sym$1 is
                .endif                  ;not defined and
                                        ;not assigned a value
        
                .ifndef sym$2           ;lookup symbol sym$2
                .else
                .byte   3,4             ;insert bytes if sym$1
                .endif                  ;is defined or
                                        ;is assigned a value
        
                .ifndef sym$3           ;lookup symbol sym$3
                .byte   12              ;insert this byte if sym$3


        THE ASSEMBLER                                          PAGE 1-38
        GENERAL ASSEMBLER DIRECTIVES


                .else                   ;is not defined/valued
                .byte   13              ;insert this byte if sym$3
                .endif                  ;is defined/valued


        All .if/.else/.endif directives are limited to a maximum nesting
        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.33  .ifb Directive 

        Format:  

                .ifb    sym
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the test condition.  

           The  conditional  .ifb  is most useful when used in macro de-
        finitions to determine if the argument is blank.  The  range  of
        true  condition  will be processed if the symbol 'sym' is blank.
        The range of true condition is optional as is the  .else  direc-
        tive  and  the  range of false condition.  The following are all
        valid .ifb/.else/.endif constructions:  

                .ifb    sym$1           ;argument is not blank
                .byte   1,2             ;insert bytes if argument
                .endif                  ;is blank
        
                .ifb    sym$2           ;argument is not blank
                .else
                .byte   3,4             ;insert bytes if argument
                .endif                  ;is not blank
        
                .ifb                    ;argument is blank
                .byte   12              ;insert this byte if
                .else                   ;argument is blank
                .byte   13              ;insert this byte if
                .endif                  ;argument not blank


        THE ASSEMBLER                                          PAGE 1-39
        GENERAL ASSEMBLER DIRECTIVES




        All .if/.else/.endif directives are limited to a maximum nesting
        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.34  .ifnb Directive 

        Format:  

                .ifnb   sym
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the test condition.  

           The  conditional  .ifnb is most useful when used in macro de-
        finitions to determine if the argument is not blank.  The  range
        of  true  condition will be processed if the symbol 'sym' is not
        blank.  The range of true condition is optional as is the  .else
        directive  and  the range of false condition.  The following are
        all valid .ifnb/.else/.endif constructions:  

                .ifnb   sym$1           ;argument is not blank
                .byte   1,2             ;insert bytes if argument
                .endif                  ;is not blank
        
                .ifnb   sym$2           ;argument is not blank
                .else
                .byte   3,4             ;insert bytes if argument
                .endif                  ;is blank
        
                .ifnb                   ;argument is blank
                .byte   12              ;insert this byte if
                .else                   ;argument is not blank
                .byte   13              ;insert this byte if
                .endif                  ;argument is blank


        All .if/.else/.endif directives are limited to a maximum nesting


        THE ASSEMBLER                                          PAGE 1-40
        GENERAL ASSEMBLER DIRECTIVES


        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.35  .ifidn Directive 

        Format:  

                .ifidn  sym$1,sym$2
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the test condition.  

           The  conditional .ifidn is most useful when used in macro de-
        finitions to determine if  the  arguments  are  identical.   The
        range  of true condition will be processed if the symbol 'sym$1'
        is idendical to 'sym$2' (i.e.  the character strings  for  sym$1
        and  sym$2  are  the  same  consistent with the case sensitivity
        flag).  When this if statement occurs inside a  macro  where  an
        argument  substitution  may  be blank then an argument should be
        delimited with the form /symbol/ for each symbol.  The range  of
        true  condition  is  optional  as is the .else directive and the
        range  of  false  condition.   The  following  are   all   valid
        .ifidn/.else/.endif constructions:  

                .ifidn  sym$1,sym$1     ;arguments are the same
                .byte   1,2             ;insert bytes if arguments
                .endif                  ;are the sane
        
                .ifidn  sym$1,sym$2     ;arguments are not the same
                .else
                .byte   3,4             ;insert bytes if arguments
                .endif                  ;are not the same
        
                .ifidn  sym$3,sym$3     ;arguments are the same
                .byte   12              ;insert this byte if
                .else                   ;arguments are the same
                .byte   13              ;insert this byte if
                .endif                  ;arguments are not the same


        THE ASSEMBLER                                          PAGE 1-41
        GENERAL ASSEMBLER DIRECTIVES




        All .if/.else/.endif directives are limited to a maximum nesting
        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.36  .ifdif Directive 

        Format:  

                .ifdif  sym$1,sym$2
                .                       ;}
                .                       ;} range of true condition
                .                       ;}
                .else
                .                       ;}
                .                       ;} range of false condition
                .                       ;}
                .endif

           The  conditional  assembly directives allow you to include or
        exclude blocks of source code during the assembly process, based
        on the evaluation of the test condition.  

           The  conditional .ifdif is most useful when used in macro de-
        finitions to determine if  the  arguments  are  different.   The
        range  of true condition will be processed if the symbol 'sym$1'
        is different from 'sym$2' (i.e.  the character strings for sym$1
        and  sym$2  are the not the same consistent with the case sensi-
        tivity flag).  When this if  statement  occurs  inside  a  macro
        where  an  argument  substitution  may be blank then an argument
        should be delimited with the form /symbol/ for each symbol.  The
        range  of  true  condition is optional as is the .else directive
        and the range of false condition.  The following are  all  valid
        .ifdif/.else/.endif constructions:  

                .ifdif  sym$1,sym$2     ;arguments are different
                .byte   1,2             ;insert bytes if arguments
                .endif                  ;are different
        
                .ifdif  sym$1,sym$1     ;arguments are identical
                .else
                .byte   3,4             ;insert bytes if arguments
                .endif                  ;are different
        
                .ifdif  sym$1,sym$3     ;arguments are different
                .byte   12              ;insert this byte if
                .else                   ;arguments are different


        THE ASSEMBLER                                          PAGE 1-42
        GENERAL ASSEMBLER DIRECTIVES


                .byte   13              ;insert this byte if
                .endif                  ;arguments are identical


        All .if/.else/.endif directives are limited to a maximum nesting
        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.37  Alternate .if Directive Forms 


           Format:  

                .if     cnd(,)  arg1(, arg2)

           where  the  cnd (followed by an optional comma) may be any of
        the following:  

                -------------------------------------------------------
                 condition              Assemble
                (complement)    Args    Block if:
                -------------------------------------------------------
                eq   ( ne )     expr    equal to zero
                                        (not equal to zero)
        
                gt   ( le )     expr    greater than zero
                                        (less than or equal to zero)
        
                lt   ( ge )     expr    less than zero
                                        (greater than or equal to zero)
        
                def  ( ndef )   symbol  .define'd or user set
                                        (not .define'd or user set)
        
                b    ( nb )     macro   argument present
                                symbol  (argument not present)
        
                idn  ( dif )    macro   arguments identical
                                symbol  (arguments not identical)
        
                f    ( t )      -----   only within a .if/.else/.endif
                                        conditional block
        
                tf              -----   only within a .if/.else/.endif
                                        conditional block


        All .if/.else/.endif directives are limited to a maximum nesting


        THE ASSEMBLER                                          PAGE 1-43
        GENERAL ASSEMBLER DIRECTIVES


        of 10 levels.  

           The  use of a .else directive outside a .if/.endif block will
        generate an (i) error.  Assemblies having unequal .if and .endif
        counts will cause an (i) error.  


        1.4.38  Immediate Conditional Assembly Directives 


           The  immediate conditional assembly directives allow a single
        line of code to be assembled without  using  a  .if/.else/.endif
        construct.   All  of  the previously described conditionals have
        immediate equivalents.  

           Format:  

                .iif            arg(,)          line_to_assemble
                .iifeq          arg(,)          line_to_assemble
                .iifne          arg(,)          line_to_assemble
                .iifgt          arg(,)          line_to_assemble
                .iifle          arg(,)          line_to_assemble
                .iifge          arg(,)          line_to_assemble
                .iiflt          arg(,)          line_to_assemble
                .iifdef         arg(,)          line_to_assemble
                .iifndef        arg(,)          line_to_assemble
        
                .iifb        (,)arg(,)          line_to_assemble
                .iifnb       (,)arg(,)          line_to_assemble
                .iifidn      (,)arg1,arg2(,)    line_to_assemble
                .iifdif      (,)arg1,arg2(,)    line_to_assemble
        
                .iiff                           line_to_assemble
                .iift                           line_to_assemble
                .iiftf                          line_to_assemble


        Alternate Format:  

                .iif            arg(,)          line_to_assemble
                .iif    eq      arg(,)          line_to_assemble
                .iif    ne      arg(,)          line_to_assemble
                .iif    gt      arg(,)          line_to_assemble
                .iif    le      arg(,)          line_to_assemble
                .iif    ge      arg(,)          line_to_assemble
                .iif    lt      arg(,)          line_to_assemble
                .iif    def     arg(,)          line_to_assemble
                .iif    ndef    arg(,)          line_to_assemble
        
                .iif    b    (,)arg(,)          line_to_assemble
                .iif    nb   (,)arg(,)          line_to_assemble
                .iif    idn  (,)arg1,arg2(,)    line_to_assemble


        THE ASSEMBLER                                          PAGE 1-44
        GENERAL ASSEMBLER DIRECTIVES


                .iif    dif  (,)arg1,arg2(,)    line_to_assemble
        
                .iiff                           line_to_assemble
                .iift                           line_to_assemble
                .iiftf                          line_to_assemble


        The (,) indicates an optional comma.  

           The  .iif  types b, n, idn, and dif require the commas if the
        argument(s) may be blank.  These commas may be  removed  if  the
        arguments are delimited with the form ^/symbol/ for each symbol. 

           The   immediate   conditional  directives  donot  change  the
        .if/.else/.endif nesting level.  


        1.4.39  .include Directive 

        Format:

                .include         /string/               or 

                .include        ^/string/ 


        where:  string  represents  a string that is the file specifica-
                        tion of an ASxxxx source file.  

                /  /    represent   the  delimiting  characters.   These
                        delimiters   may   be   any   paired    printing
                        characters,  as  long  as the characters are not
                        contained within  the  string  itself.   If  the
                        delimiting characters do not match, the .include
                        directive will give the (q) error.  

           The .include directive is used to insert a source file within
        the source file currently being assembled.  When this  directive
        is encountered, an implicit .page directive is issued.  When the
        end of the specified source file is reached, an  implicit  .page
        directive is issued and input continues from the previous source
        file.  The maximum nesting level of source files specified by  a
        .include directive is five.

           The  total  number  of separately specified .include files is
        unlimited as each .include file is opened and then closed during
        each pass made by the assembler.  

           The  default  directory  path,  if none is specified, for any
        .include file is the directory path of the  current  file.   For
        example:    if   the  current  source  file,  D:\proj\file1.asm,


        THE ASSEMBLER                                          PAGE 1-45
        GENERAL ASSEMBLER DIRECTIVES


        includes  a  file  specified  as  "include1"   then   the   file
        D:\proj\include1.asm is opened.  




        THE ASSEMBLER                                          PAGE 1-46
        GENERAL ASSEMBLER DIRECTIVES


        1.4.41  .setdp Directive 

        Format:

                .setdp [base [,area]]

        The set direct page directive has a common format in all the as-
        semblers supporting a paged mode.  The .setdp directive is  used
        to  inform  the  assembler of the current direct page region and
        the offset address within the selected area.  The normal invoca-
        tion methods are:  

                .area   DIRECT  (PAG)
                .setdp

                or

                .setdp  0,DIRECT

        for  all  the  68xx microprocessors (the 6804 has only the paged
        ram area).  The commands specify that the direct page is in area
        DIRECT and its offset address is 0 (the only valid value for all
        but the 6809 microprocessor).  Be sure to place the DIRECT  area
        at address 0 during linking.  When the base address and area are
        not specified, then zero and the current area are the  defaults.
        If  a  .setdp directive is not issued the assembler defaults the
        direct page to the area "_CODE" at offset 0.

           The  assembler  verifies  that  any  local variable used in a
        direct variable reference is located in this area.  Local  vari-
        able  and  constant value direct access addresses are checked to
        be within the address range from 0 to 255.

           External direct references are assumed by the assembler to be
        in the correct area and have valid  offsets.   The  linker  will
        check all direct page relocations to verify that they are within
        the correct area.

           The  6809  microprocessor  allows the selection of the direct
        page to be on any 256 byte boundary by loading  the  appropriate
        value  into the dp register.  Typically one would like to select
        the page boundary at link time, one method follows:


        THE ASSEMBLER                                          PAGE 1-47
        GENERAL ASSEMBLER DIRECTIVES


                .area   DIRECT  (PAG)   ; define the direct page
                .setdp
                .
                .
                .
                .area   PROGRAM
                .
                ldd     #DIRECT         ; load the direct page register
                tfr     a,dp            ; for access to the direct page

        At  link  time specify the base and global equates to locate the
        direct page:

                -b DIRECT = 0x1000
                -g DIRECT = 0x1000

        Both  the  area address and offset value must be specified (area
        and variable names are independent).   The  linker  will  verify
        that  the  relocated  direct page accesses are within the direct
        page.

        The  preceeding  sequence  could  be repeated for multiple paged
        areas, however an alternate method is to define a non-paged area
        and use the .setdp directive to specify the offset value:

                .area   DIRECT          ; define non-paged area
                .
                .
                .
                .area   PROGRAM
                .
                .setdp  0,DIRECT        ; direct page area
                ldd     #DIRECT         ; load the direct page register
                tfr     a,dp            ; for access to the direct page
                .
                .
                .setdp  0x100,DIRECT    ; direct page area
                ldd     #DIRECT+0x100   ; load the direct page register
                tfr     a,dp            ; for access to the direct page

        The  linker  will  verify that subsequent direct page references
        are in the specified area and offset address range.  It  is  the
        programmers responsibility to load the dp register with the cor-
        rect page segment  corresponding  to  the  .setdp  base  address
        specified.

           For  those  cases  where a single piece of code must access a
        defined data structure within a direct page and there  are  many
        pages,  define  a  dumby  direct page linked at address 0.  This
        dumby page is used only to define  the  variable  labels.   Then
        load  the dp register with the real base address but donot use a
        .setdp  directive.   This  method  is  equivalent   to   indexed


        THE ASSEMBLER                                          PAGE 1-48
        GENERAL ASSEMBLER DIRECTIVES


        addressing,  where the dp register is the index register and the
        direct addressing is the offset.


        1.4.42  .16bit, .24bit, and .32bit Directives 

        Format:  

                .16bit          ;specify 16-bit addressing
                .24bit          ;specify 24-bit addressing
                .32bit          ;specify 32-bit addressing


           The  .16bit, .24bit, and .32bit directives are special direc-
        tives for assembler configuration when default  values  are  not
        used.  


        1.5  INVOKING ASXXXX


           Starting  an  ASxxxx assembler without any arguments provides
        the following option list and then exits:  

        Usage: [-Options] file
        Usage: [-Options] outfile file1 [file2 file3 ...]
          -d   Decimal listing
          -q   Octal   listing
          -x   Hex     listing (default)
          -g   Undefined symbols made global
          -a   All user symbols made global
          -b   Display .define substitutions in listing
          -bb  and display without .define substitutions
          -c   Disable instruction cycle count in listing
          -j   Enable NoICE Debug Symbols
          -y   Enable SDCC  Debug Symbols
          -l   Create list   output (out)file[.lst]
          -o   Create object output (out)file[.rel]
          -s   Create symbol output (out)file[.sym]
          -p   Disable listing pagination
          -u   Disable .list/.nlist processing
          -w   Wide listing format for symbol table
          -z   Disable case sensitivity for symbols
          -f   Flag relocatable references by  `   in listing file
          -ff  Flag relocatable references by mode in listing file



           The ASxxxx assemblers are command line oriented.  Most sytems
        require the option(s) and file(s) arguments to follow the ASxxxx
        assembler name:  

          as6809 -[Options] file
        
          as6809 [-Options] outfile file1 [file2 ...]


        Some  systems  may  request the arguments after the assembler is
        started at a system specific prompt:  

          as6809
          argv: -[Options] file
        
          as6809
          argv: [-Options] outfile file1 [file2 ...]


        The ASxxxx options in some more detail:  

                -d      decimal listing


        THE ASSEMBLER                                          PAGE 1-51
        INVOKING ASXXXX


                -q      octal   listing
                -x      hex     listing (default)

                        The listing radix affects the
                        .lst, .rel, and .sym files.

                -g      undefined symbols made global
        
                        Unresolved (external) variables
                        and symbols are flagged as global.
        
                -a      all user symbols made global
        
                        All defined (not local or external)
                        variables and symbols are flagged
                        as global.
        
                -b      display .define substitutions in listing
        
                        If a .define substitution has been applied
                        to an assembler source line the source
                        line is printed with the substitution.
        
                -bb     and display without .define substitutions
        
                        If a .define substitution has been applied
                        to an assembler source line the source
                        line is first printed without substitution
                        followed by the line with the substitution.
        
                -c      Disable instruction cycle count in listing
        
                        This option overrides the listing option
                        'cyc' in the .list and .nlist directives.
                        Instruction cycle counts cannot be enabled
                        if the -c option is specified.
        
                -j      enable NOICE debug symbols
                -y      enable SDCC debug symbols
        
                -l      create list   output (out)file.lst
        
                        If -s (symbol table output) is not
                        specified the symbol table is included
                        at the end of the listing file.
        
                -o      create object output (out)file.rel
                -s      create symbol output (out)file.sym
        
                -p      disable listing pagination
        
                        This option inhibits the generation


        THE ASSEMBLER                                          PAGE 1-52
        INVOKING ASXXXX


                        of a form-feed character and its
                        associated page header in the
                        assembler listing.
        
                -u      disable .list/.nlist processing
        
                        This option disables all .list and
                        .nlist directives. The listing mode
                        is .list with the options err, loc,
                        bin, eqt, cyc, lin, src, pag, lst,
                        and md. The options cyc and pag are
                        overridden by the -c and -p command
                        line options.
        
                -w      wide listing format for symbol table
        
                -z      disable case sensitivity for symbols
        
                -f      by  `   in the listing file
                -ff     by mode in the listing file
        
                        Relocatable modess are flagged by byte
                        position (LSB, Byte 2, Byte 3, MSB)
                        *nMN    paged,
                        uvUV    unsigned,
                        rsRS    signed,
                        pqPQ    program counter relative.

        asx8051 specific command line option:
                -I<dir>  Add the named directory to the include file
                        search path.  This option may be used more than once.
                        Directories are searched in the order given.

           The file name for the .lst, .rel, and .sym files is the first
        file name specified in the command line.  All output  files  are
        ascii  text  files which may be edited, copied, etc.  The output
        files are the concatenation of all the input files, if files are
        to  be  assembled  independently  invoke  the assembler for each
        file.

           The  .rel  file contains a radix directive so that the linker
        will use the proper conversion for this file.  Linked files  may
        have different radices.

        ASXXXX assemblers supported by and distributed with SDCC are:
                sdas390         (Dallas 80390)
                sdas6808        (Motorola 68HC08)
                sdas8051        (Intel 8051)
                sdasgb          (GameBoy Z80-like CPU)
                sdasrab         (Rabbit Z80-like CPU)
                sdasz80         (Zilog Z80 / Hitachi HD64180)


        1.6  ERRORS


           The  ASxxxx assemblers provide limited diagnostic error codes
        during the assembly process, these errors will be noted  in  the
        listing file and printed on the stderr device.

           The assembler reports the errors on the stderr device as

                ?ASxxxx-Error-<*> in line nnn of filename

        where  * is the error code, nnn is the line number, and filename


        THE ASSEMBLER                                          PAGE 1-53
        ERRORS


        is the source/include file.

           The errors are:

              (.)   This  error  is caused by an absolute direct assign-
                    ment of the current location counter
                          . = expression (incorrect)
                    rather than the correct
                          . = . + expression

              (a)   Indicates  a machine specific addressing or address-
                    ing mode error.

              (b)   Indicates a direct page boundary error.

              (d)   Indicates a direct page addressing error.

              (i)   Caused  by  an  .include file error or an .if/.endif
                    mismatch.

              (m)   Multiple  definitions  of  the  same label, multiple
                    .module directives, multiple conflicting  attributes
                    in an .area directive.

              (n)   An  .mexit,  .endm,  or .narg directive outside of a
                    macro, repeat block or indefinite repeat block.  

              (o)   Directive  or  mnemonic error or the use of the .org
                    directive in a relocatable area.

              (p)   Phase error:  label location changing between passes
                    2 and 3.  Normally caused by having  more  than  one
                    level of forward referencing.

              (q)   Questionable syntax:  missing or improper operators,
                    terminators, or delimiters.

              (r)   Relocation  error:   logic  operation attempted on a
                    relocatable term, addition of two relocatable terms,
                    subtraction  of two relocatable terms not within the
                    same programming area or external symbols.

              (s)   String Substitution / recursion error.  

              (u)   Undefined symbol encountered during assembly.

              (z)   Divide by 0 or Modulus by 0 error:  result is 0.  




        THE ASSEMBLER                                          PAGE 1-54
        LISTING FILE


        1.7  LISTING FILE


           The  (-l) option produces an ascii output listing file.  Each
        page of output contains a five line header:  


             1.  The ASxxxx program name and page number

             2.  Assembler Radix and Address Bits 

             3.  Title from a .title directive (if any) 

             4.  Subtitle from a .sbttl directive (if any) 

             5.  Blank line 



        Each succeeding line contains six fields:  


             1.  Error field (first two characters of line) 

             2.  Current location counter

             3.  Generated code in byte format

             4.  Opcode cycles count 

             5.  Source text line number 

             6.  Source text 


           The error field may contain upto 2 error flags indicating any
        errors encountered while assembling this line of source code.

           The  current  location  counter  field  displays  the 16-bit,
        24-bit, or 32-bit program position.  This field will be  in  the
        selected radix.  

           The generated code follows the program location.  The listing
        radix determines the number of bytes that will be  displayed  in
        this field.  Hexadecimal listing allows six bytes of data within
        the field, decimal and octal allow four bytes within the  field.
        If more than one field of data is generated from the assembly of
        a single line of source code, then the data field is repeated on
        successive lines.

           The  opcode cycles count is printed within the delimiters [ ]
        on the line with the source text.  This reduces  the  number  of


        THE ASSEMBLER                                          PAGE 1-55
        LISTING FILE


        generated code bytes displayed on the line with the source list-
        ing by one.  (The -c option disables all opcode cycle listing.) 

           The source text line number is printed in decimal and is fol-
        lowed by the source text.  A Source line with a .page  directive
        is never listed.  (The -u option overrides this behavior.) 

           Two  additional options are available for printing the source
        line text.  If the -b option is specified then the listed source
        line  contains all the .define substitutions.  If the -bb option
        is specified then the original source line is printed before the
        source line with substitutions.  

           Two  data  field  options  are  available to flag those bytes
        which will be relocated by the linker.   If  the  -f  option  is
        specified  then  each  byte to be relocated will be preceeded by
        the '`' character.  If the -ff option  is  specified  then  each
        byte  to  be relocated will be preceeded by one of the following
        characters:

             1.  *   paged relocation

             2.  u   low  byte of unsigned word or unsigned byte

             3.  v   high byte of unsigned word

             4.  p   PCR low  byte of word relocation or PCR byte

             5.  q   PCR high byte of word relocation

             6.  r   low  byte relocation or byte relocation

             7.  s   high byte relocation


           Assemblers  which  use 24-bit or 32-bit addressing use an ex-
        tended flagging mode:  

             1.  *   paged relocation 

             2.  u   1st  byte of unsigned value 

             3.  v   2nd  byte of unsigned value 

             4.  U   3rd  byte of unsigned value 

             5.  V   4th  byte of unsigned value 

             6.  p   PCR 1st  byte of relocation value or PCR byte 

             7.  q   PCR 2nd  byte of relocation value 



        THE ASSEMBLER                                          PAGE 1-56
        LISTING FILE


             8.  P   PCR 3rd  byte of relocation value 

             9.  Q   PCR 4th  byte of relocation value 

            10.  r   1st  byte of relocation value or byte relocation 

            11.  s   2nd  byte of relocation value 

            12.  R   3rd  byte of relocation value 

            13.  S   4th  byte of relocation value 



        1.8  SYMBOL TABLE FILE


           The symbol table has two parts:

             1.  The alphabetically sorted list of symbols and/or labels
                 defined or referenced in the source program.

             2.  A  list of the program areas defined during assembly of
                 the source program.


           The sorted list of symbols and/or labels contains the follow-
        ing information:

             1.  Program  area  number (none if absolute value or exter-
                 nal)

             2.  The symbol or label

             3.  Directly assigned symbol is denoted with an (=) sign

             4.  The  value of a symbol, location of a label relative to
                 the program area base address (=0), or a ****  indicat-
                 ing the symbol or label is undefined.

             5.  The       characters:       G - global,      L - local,
                 R - relocatable, and X - external.  


           The list of program areas provides the correspondence between
        the program area numbers and the defined program areas, the size
        of the program areas, and the area flags (attributes).




        THE ASSEMBLER                                          PAGE 1-57
        OBJECT FILE


        1.9  OBJECT FILE


           The  object  file is an ascii file containing the information
        needed by the linker to bind multiple object modules into a com-
        plete  loadable  memory  image.   The object module contains the
        following designators:

                [XDQ][HL][234]
                        X       Hexadecimal radix
                        D       Decimal radix
                        Q       Octal radix

                        H       Most significant byte first
                        L       Least significant byte first

                        2       16-Bit Addressing
                        3       24-Bit Addressing
                        4       32-Bit Addressing
        
                H       Header
                M       Module
                A       Area
                S       Symbol
                T       Object code
                R       Relocation information
                P       Paging information

           Refer to the linker for a detailed description of each of the
        designators and the format of the information contained  in  the
        object file.














                                    CHAPTER 2

                               THE MACRO PROCESSOR





        2.1  DEFINING MACROS 


           By  using macros a programmer can use a single line to insert
        a sequence of lines into a source program.  

           A  macro  definition is headed by a .macro directive followed
        by the source lines.  The source lines  may  optionally  contain
        dummy arguments.  If such arguments are used, each one is listed
        in the .macro directive.  

           A  macro call is the statement used by the programmer to call
        the macro source program.  It consists of the  macro  name  fol-
        lowed  by  the  real arguments needed to replace the dummy argu-
        ments used in the macro.  

           Macro  expansion  is  the insertion of the macro source lines
        into the main  program.   Included  in  this  insertion  is  the
        replacement of the dummy arguments by the real arguments.  

           Macro  directives provide a means to manipulate the macro ex-
        pansions.  Only one directive is allowed per source line.   Each
        directive  may  have  a  blank  operand  field  or  one  or more
        operands.  Legal  operands  differ  with  each  directive.   The
        macros  and  their  associated  directives  are detailed in this
        chapter.  

           Macro  directives  can replace any machine dependent mnemonic
        associated with a specific assembler.  However, the basic assem-
        bler directives cannot be replaced with a macro.  


        THE MACRO PROCESSOR                                     PAGE 2-2
        DEFINING MACROS


        2.1.1  .macro Directive 


        Format:
        
        [label:]        .macro  name, dummy argument list
        
        where:  label   represents an optional statement label.
        
                name    represents the user-assigned symbolic
                        name of the macro.  This name  may be
                        any legal symbol and may be used as a
                        label elsewhere in the program.  The
                        macro name is not case sensitive,
                        name, NAME, or nAmE all refer to the
                        same macro.
        
                ,       represents a legal macro separator
                        (comma, space, and/or tab).
        
                dummy   represents a number of legal symbols
               argument that may appear anywhere in the body of
                list    the macro definition,  even as a label.
                        These dummy symbols can be used elsewhere
                        in the program with no conflict of
                        definition.  Multiple dummy arguments
                        specified in this directive may be
                        separated by any legal separator.  The
                        detection of a duplicate or an illegal
                        symbol in a dummy argument list
                        terminates the scan and causes a 'q'
                        error to be generated.


        A  comment may follow the dummy argument list in a .macro direc-
        tive, as shown below:  

                .macro  abs     a,b     ;Defines macro abs


        The  first  statement  of  a  macro  definition must be a .macro
        directive.  Defining a macro with the same name as  an  existing
        macro will generate an 'm' error.  The .mdelete directive should
        be used to delete the previous macro definition before  redefin-
        ing a macro.  




        THE MACRO PROCESSOR                                     PAGE 2-3
        DEFINING MACROS


        2.1.2  .endm Directive 


        Format:
        
                .endm


        The .endm directive should not have a label.  Because the direc-
        tives .irp, .irpc, and .rept may repeat more than once the label
        will  be  defined multiple times resulting in 'm' and/or 'p' er-
        rors.  

           The  .endm  directive  may be followed by a comment field, as
        shown below:  

                .endm           ;end of macro

           A  comment  may  follow  the  dummy argument list in a .macro
        directive, as shown below:  

                .macro  typemsg message ;Type a message.
                jsr     typemsg
                .word   message
                .endm                   ;End of typemsg


        The  final  statement  of every macro definition must be a .endm
        directive.  The .endm directive is also used to terminate  inde-
        finite  repeat  blocks and repeat blocks.  A .endm directive en-
        countered outside a macro definition  is  flagged  with  an  'n'
        error.  


        2.1.3  .mexit Directive 


        Format:
        
                .mexit


        The  .mexit directive may be used to terminate a macro expansion
        before the end of the macro is encountered.  This  directive  is
        also  legal  within  repeat blocks.  It is most useful in nested
        macros.  The .mexit directive terminates the  current  macro  as
        though a .endm directive had been encountered.  Using the .mexit
        directive bypasses the complexities of nested conditional direc-
        tives  and  alternate  assembly paths, as shown in the following
        example:  



        THE MACRO PROCESSOR                                     PAGE 2-4
        DEFINING MACROS


                .macro  altr    N,A,B
                  .
                  .
                  .
                .if eq,N        ;Start conditional Block
                  .
                  .
                  .
                .mexit          ;Terminate macro expansion
                .endif          ;End of conditional block
                  .
                  .
                  .
                .endm           ;Normal end of macro


        In  an  assembly  where  the  symbol  N is replaced by zero, the
        .mexit directive would assemble the conditional block  and  ter-
        minate  the  macro  expansion.   When macros ar nested, a .mexit
        directive causes an exit to the next higher level of  macro  ex-
        pansion.  A .mexit directive encountered outside a macro defini-
        tion is flagged with an 'n' error.  


        2.2  CALLING MACROS 


        Format:
        
                [label:]  name  real arguments
        
        where:  label   represents an optional statement label.
        
                name    represents the name of the macro, as
                        specified in the macro definition.
        
                real    represent symbolic arguments which
             arguments  replace the dummy arguments listed
                        in the .macro definition.  When
                        multiple arguments occur, they are
                        separated by any legal separator.
                        Arguments to the macro call are
                        treated as character strings, their
                        usage is determined by the macro
                        definition.

        A  macro  definition  must be established by means of the .macro
        directive before the macro can be called and expanded within the
        source program.  

           When a macro name is the same as a user label, the appearance
        of the symbol in the operator field designates the symbol  as  a


        THE MACRO PROCESSOR                                     PAGE 2-5
        CALLING MACROS


        macro  call;   the appearance of the symbol in the operand field
        designates it as a label, as shown below:  

        LESS:   mov     @r0,r1          ;LESS is a label
                 .
                 .
                 .
                bra     LESS            ;LESS is considered a label
                 .
                 .
                 .
                LESS    sym1,sym2       ;LESS is a macro call


        2.3  ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS 


           Multiple arguments within a macro must be separated by one of
        the legal separating characters (comma, space, and/or tab).  

           Macro  definition  arguments (dummy) and macro call arguments
        (real) maintain a strict positional relationship.  That is,  the
        first  real  argument in a macro call corresponds with the first
        dummy argument in the macro definition.  

           For  example,  the  following  macro definition and its asso-
        ciated macro call contain multiple arguments:  

                .macro  new     a,b,c
                  .
                  .
                  .
        
                new     phi,sig,^/C1,C2/


        Arguments which themselves contain separating characters must be
        enclosed  within  the  delimiter  construct  ^/   /  where   the
        character  '/'  may be any character not in the argument string.
        For example, the macro call:  

                new     ^/exg    x,y/,#44,ij

        causes the entire expression 

                exg    x,y

        to  replace all occurrances of the symbol a in the macro defini-
        tion.  Real arguments with a macro call  are  considered  to  be
        character  strings  and  are  treated  as a single entity during
        macro expansion.  



        THE MACRO PROCESSOR                                     PAGE 2-6
        ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS


           The  up-arrow  (^)  construction also allows another up-arrow
        costruction to be passed as part of  the  argument.   This  con-
        struction,  for example, could have been used in the above macro
        call, as follows:  

                new     ^!^/exg    x,y/!,#44,ij

        causing the entire string ^/exg    x,y/ to be passed as an argu-
        ment.  


        2.3.1  Macro Nesting 


           Macro  nesting  occurs  where  the expansion of one macro in-
        cludes a call to another macro.  The depth of nesting  is  arbi-
        trarily limited to 20.  

           To  pass  an argument containing legal argument delimiters to
        nested macros, enclose the  argument  in  the  macro  definition
        within  an up-arrow construction, as shown in the coding example
        below.  This extra set of delimiters for each level  of  nesting
        is required in the macro definition, not the in the macro call. 

                .macro  level1  dum1,dum2
                level2  ^/dum1/
                level2  ^/dum2/
                .endm
        
                .macro  level2  dum3
                dum3
                add     #10,z
                push    z
                .endm

        A call to the level1 macro, as shown below, for example:  

                level1  ^/leaz    0,x/,^/tfr     x,z/

        causes the following macro expansion to occur:  

                leaz    0,x
                add     #10,z
                push    z
                tfr     x,z
                add     #10,z
                push    z

        When  macro  definitions are nested, the inner definition cannot
        be called until the outer macro has been  called  and  expanded.
        For example, in the following code:  



        THE MACRO PROCESSOR                                     PAGE 2-7
        ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS


                .macro  lv1     a,b
                  .
                  .
                  .
                .macro  lv2     c
                  .
                  .
                  .
                .endm
                .endm

        the  lv2 macro cannot be called and expanded until the lv1 macro
        has been expanded.  Likewise, any macro defined within  the  lv2
        macro  definition  cannot  be  called and expanded until lv2 has
        also been expanded.  


        2.3.2  Special Characters in Macro Arguments 


           If  an  argument  does not contain spaces, tabs, or commas it
        may include special  characters  without  enclosing  them  in  a
        delimited construction.  For example:  

                .macro  push    arg
                mov     arg,-(sp)
                .endm
        
        
                push    x+3(%2)

        causes the following code to be generated:  

                mov     x+3(%2),-(sp)


        2.3.3  Passing Numerical Arguments as Symbols 


           If the unary operator backslash (\) precedes an argument, the
        macro treats the argument as a numeric value in the current pro-
        gram  radix.   The  ascii characters representing this value are
        inserted in the macro expansion, and their function  is  defined
        in  the context of the resulting code, as shown in the following
        example:  



        THE MACRO PROCESSOR                                     PAGE 2-8
        ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS


                .macro  inc     a,b
                con     a,\b
                b = b + 1
                .endm
        
                .macro  con     a,b
        a'b:    .word   4
                .endm
        
                ...
        
                c = 0           ;Initialize
        
                inc     x,c

        The above macro call (inc) would thus expand to:  

                x0:     .word   4

        In  this  expanded  code,  the  lable x0:  results from the con-
        catenation  of  two  real  arguments.   The  single  quote   (')
        character  in  the  label a'b:  concatenates the real argument x
        and 0 as they are passed during  the  expansion  of  the  macro.
        This type of argument construction is descibed in more detail in
        a following section.  

           A  subsequent  call to the same macro would generate the fol-
        lowing code:  

                x1:     .word   4

        and  so  on,  for  later  calls.   The two macro definitions are
        necessary because the symbol associated with the dummy  argument
        b (that is, symbol c) cannot be updated in the con macro defini-
        tion, because the character 0 has replaced  c  in  the  argument
        string  (inc  x,c).   In  the  con  macro definition, the number
        passed is treated as a string argument.  (Where the value of the
        real  argument  is 0, only a single 0 character is passed to the
        macro expansion.  




        THE MACRO PROCESSOR                                     PAGE 2-9
        ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS


        2.3.4  Number of Arguments in Macro Calls 


           A  macro  can  be defined with or without arguments.  If more
        arguments appear in the macro call than in the macro definition,
        a  'q'  error  is  generated.   If fewer arguments appear in the
        macro call than in the macro definition, missing  arguments  are
        assumed to be null values.  The conditional directives .if b and
        .if nb can be used within the macro to detect missing arguments.
        The number of arguments can be determined using the .narg direc-
        tive.  


        2.3.5  Creating Local Symbols Automatically 


           A  label is often required in an expanded macro.  In the con-
        ventional macro facilituies thus far described, a label must  be
        explicitly  specified  as an argument with each macro call.  The
        user must be careful in issuing subsequent  calls  to  the  same
        macro  in  order  avoid duplicating labels.  This concern can be
        eliminated through a feature of the ASxxxx macro  facility  that
        creates a unique symbol where a label is required in an expanded
        macro.  

           ASxxxx  allows temporary symbols of the form n$, where n is a
        decimal integer.  Automatically created symbols are  created  in
        numerical order beginning at 10000$.  

           The  automatic generation of local symbols is invoked on each
        call of a macro whose definition contains a dummy argument  pre-
        ceded  by the question mark (?) character, as shown in the macro
        definition below:  

                .macro  beta    a,?b    ;dummy argument b with ?
                tst     a
                beq     b
                add     #5,a
        b:
                .endm


           A  local symbol is created automatically only when a real ar-
        gument of the macro call is either null or missing, as shown  in
        Example 1 below.  If the real argument is specified in the macro
        call, however, generation of the local symbol is  inhibited  and
        normal argument replacement occurs, as shown in Example 2 below.
        (Examples 1 and 2 are both expansions of the beta macro  defined
        above.) 



        THE MACRO PROCESSOR                                    PAGE 2-10
        ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS


        Example 1:  Create a Local Symbol for the Missing Argument
        
                beta    flag    ;Second argument is missing.
                tst     flag
                beq     10000$  ;Local symbol is created.
                add     #5,flag
        10000$:
        
        Example 2:  Do Not Create a Local Symbol
        
                beta    r3,xyz
                tst     r3
                beq     xyz
                add     #5,r3
        xyz:


           Automatically created local symbols resulting from the expan-
        sion of a macro, as described above, do not  establish  a  local
        symbol block in their own right.  

           When  a  macro  has several arguments earmarked for automatic
        local symbol generation, substituting a specific label  for  one
        such  argument  risks  assembly errors because the arguments are
        constructed at the point of macro invocation.  Therefor, the ap-
        pearance of a label in the macro expansion will create a new lo-
        cal symbol block.  The new local symbol block could leave  local
        symbol references in the previous block and their symbol defini-
        tions in the new one, causing error codes in the assembly  list-
        ing.   Furthermore  a  later  macro expansion that creates local
        symbols in the new block may duplicate one  of  the  symbols  in
        question,  causing  an additional error code 'p' in the assembly
        listing.  


        2.3.6  Concatenation of Macro Arguments 


           The  apostrophe  or  single quote character (') operates as a
        legal delimiting character in macro definitions.  A single quote
        that precedes and/or follows a dummy argument in a macro defini-
        tion is removed, and the substitution of the real  argument  oc-
        curs at that point.  For example, in the following statements:  

                .macro  def     A,B,C
        A'B:    asciz   "C"
                .byte   ''A,''B
                .endm

        when the macro def is called through the statement:  



        THE MACRO PROCESSOR                                    PAGE 2-11
        ARGUMENTS IN MACRO DEFINITIONS AND MACRO CALLS


                def     x,y,^/V05.00/

        it is expanded, as follows:  

        xy:     asciz   "V05.00"
                .byte   'x,'y

        In  expanding  the  first  line, the scan for the first argument
        terminates upon finding  the  first  apostrophe  (')  character.
        Since  A is a dummy argument, the apostrphe (') is removed.  The
        scan then resumes with B;  B is also noted as another dummy  ar-
        gument.   The  two  real  arguments x and y are then concated to
        form the label xy:.  The third dummy argument is  noted  in  the
        operand field of the .asciz directive, causing the real argument
        V05.00 to be substituted in this field.  

           When  evaluating  the arguments of the .byte directive during
        expansion of the second line, the scan  begins  with  the  first
        apostrophe (') character.  Since it is neither preceded nor fol-
        lowed by a dummy argument, this apostrophe remains in the  macro
        expansion.   The  scan  then  encounters  the second apostrophe,
        which is followed by a dummy argument and is therefor discarded.
        The scan of argument A is terminated upon encountering the comma
        (,).  The third apostrophe is neither preceded nor followed by a
        dummy  argument  and  again remains in the macro expansion.  The
        fourth (and last) apostrophe is followed by another dummy  argu-
        ment and is likewise discarded.  (Four apostrophe (') characters
        were necessary in the macro definition  to  generate  two  apos-
        trophe (') characters in the macro expansion.) 


        2.4  MACRO ATTRIBUTE DIRECTIVES 


           The  ASxxxx  assemblers  have  four directives that allow the
        user to determine certain attributes of macro arguments:  .narg,
        .nchr,  .ntyp,  and  .nval.  The use of these directives permits
        selective modifications of a macro expansion, depending  on  the
        nature  of  the  arguments  being  passed.  These directives are
        described below.  


        THE MACRO PROCESSOR                                    PAGE 2-12
        MACRO ATTRIBUTE DIRECTIVES


        2.4.1  .narg Directive 


        Format:
        
        [label:]        .narg   symbol
        
        where:  label   represents an optional statement label.
        
                symbol  represents any legal symbol. This symbol
                        is equated to the number of arguments in
                        the macro call currently being expanded.
                        If a symbol is not specified, the .narg
                        directive is flagged with a 'q' error.

        The .narg directive is used to determine the number of arguments
        in the macro call currently being expanded.   Hence,  the  .narg
        directive  can appear only within a macro definition;  if it ap-
        pears elsewhere, an 'n' error is generated.  

           The  argument  count  includes null arguments as shown in the
        following:  

                .macro  pack    A,B,C
                .narg   cnt
                  .
                  .
                  .
                .endm
        
                pack    arg1,,arg3
                pack    arg1

        When  the  first macro pack is invoked .narg will assign a value
        of three (3) to the number of arguments cnt, which includes  the
        empty  argument.  The second invocation of macro pack has only a
        single argument specified and .narg will assign a value  of  one
        (1) to cnt.  


        THE MACRO PROCESSOR                                    PAGE 2-13
        MACRO ATTRIBUTE DIRECTIVES


        2.4.2  .nchr Directive 


        Format:
        
        [label:]        .nchr   symbol,string
        
        where:  label   represents an optional statement label.
        
                symbol  represents any legal symbol. This symbol
                        is equated to the number of characters in
                        the string of the macro call currently
                        being expanded.  If a symbol is not
                        specified, the .nchr  directive is
                        flagged with a 'q' error.
        
                ,       represents any legal separator (comma,
                        space, and/or tab).
        
                string  represents a string of printable 7-bit
                        ascii characters.  If the character
                        string contains a legal separator
                        (comma, space and/or tab) the whole
                        string must be delimited using the
                        up-arrow (^) construct ^/    /.
                        If the delimiting characters do not
                        match or if the ending delimiter
                        cannot be detected because of a
                        syntactical error in the character
                        string, the .nchr directive reports
                        a 'q' error.

        The .nchr directive, which can appear anywhere in an ASxxxx pro-
        gram, is used to determine the number of characters in a  speci-
        fied  character string.  This directive is useful in calculating
        the length of macro arguments.  


        THE MACRO PROCESSOR                                    PAGE 2-14
        MACRO ATTRIBUTE DIRECTIVES


        2.4.3  .ntyp Directive 


        Format:
        
        [label:]        .ntyp   symbol,arg
        
        where:  label   represents an optional statement label.
        
                symbol  represents any legal symbol. The symbol
                        is made absolute and equated to 0 if
                        arg is an absolute value or a non
                        relocatable symbol.  The symbol is made
                        absolute and equated to 1 if arg is a
                        relocatable symbol.  If a symbol is not
                        specified then the .ntyp directive is
                        flagged with a 'q' error.
        
                ,       represents any legal separator (comma,
                        space, and/or tab).
        
                arg     represents any legal expression or
                        symbol. If arg is not specified
                        then the .ntyp directive is flagged
                        with a 'q' error.

        The .ntyp directive, which can appear anywhere in an ASxxxx pro-
        gram, is used to determine the symbol or expression type as  ab-
        solute (0) or relocatable (1).  


        2.4.4  .nval Directive 


        Format:
        
        [label:]        .nval   symbol,arg
        
        where:  label   represents an optional statement label.
        
                symbol  represents any legal symbol. The symbol
                        is equated to the value of arg and made
                        absolute.  If a symbol is not specified
                        then the .nval directive is flagged
                        with a 'q' error.
        
                ,       represents any legal separator (comma,
                        space, and/or tab).
        
                arg     represents any legal expression or
                        symbol. If arg is not specified
                        then the .nval directive is flagged


        THE MACRO PROCESSOR                                    PAGE 2-15
        MACRO ATTRIBUTE DIRECTIVES


                        with a 'q' error.

        The .nval directive, which can appear anywhere in an ASxxxx pro-
        gram, is used to determine the value of arg and make the  result
        an absolute value.  


        2.5  INDEFINITE REPEAT BLOCK DIRECTIVES 


           An  indefinite  repeat block is similar to a macro definition
        with only one dummy argument.  At each expansion  of  the  inde-
        finite  repeat  range, this dummy argument is replaced with suc-
        cessive elements of a real  argument  list.   Since  the  repeat
        directive  and its associated range are coded in-line within the
        source program, this type of macro definition and expansion does
        not require calling the macro by name, as required in the expan-
        sion of the conventional macros previously described.  

           An  indefinite  repeat  block  can  appear  within or outside
        another macro definition, indefinite  repeat  block,  or  repeat
        block.   The  rules specifying indefinite repeat block arguments
        are the same as for specifying macro arguments.  


        THE MACRO PROCESSOR                                    PAGE 2-16
        INDEFINITE REPEAT BLOCK DIRECTIVES


        2.5.1  .irp Directive 


        Format:
        
            [label:]    .irp    sym,argument_list
                        .
                        .
                    (range of indefinite repeat block)
                        .
                        .
                        .endm                   
        
        where:  label   represents an optional statement label.
        
                sym     represents a dummy argument that is
                        replaced with successive real arguments
                        from the argument list.  If the dummy
                        argument is not specified, the .irp
                        directive is flagged with a 'q' error.
        
                ,       represents any legal separator (comma,
                        space, and/or tab).
        
          argument_list represents a list of real arguments
                        that are to be used in the expansion
                        of the indefinite repeat range. A real
                        argument may consist of one or more
                        7-bit ascii characters; multiple
                        arguments must be separated by any
                        legal separator (comma, space, and/or
                        tab).  If an argument must contain
                        a legal separator then the up-arrow
                        (_^) construct is require for that
                        argument.  If no real arguments are
                        specified, no action is taken.
        
                range   represents the block of code to be
                        repeated once for each occurrence of
                        a real argument in the list.  The
                        range may contain other macro
                        definitions, repeat ranges and/or
                        the .mexit directive.
        
                .endm   indicates the end of the indefinite
                        repeat block range.

        The .irp directive is used to replace a dummy argument with suc-
        cessive real arguments specified  in  an  argument  list.   This
        replacement  process  occurrs  during  the expansion of an inde-
        finite repeat block range.  


        THE MACRO PROCESSOR                                    PAGE 2-17
        INDEFINITE REPEAT BLOCK DIRECTIVES


        2.5.2  .irpc Directive 


        Format:
        
            [label:]    .irpc   sym,string
                        .
                        .
                    (range of indefinite repeat block)
                        .
                        .
                        .endm                   
        
        where:  label   represents an optional statement label.
        
                sym     represents a dummy argument that is
                        replaced with successive real characters
                        from the argument string.  If the dummy
                        argument is not specified, the .irpc
                        directive is flagged with a 'q' error.
        
                ,       represents any legal separator (comma,
                        space, and/or tab).
        
                string  represents a list of 7-bit ascii
                        characters.  If the string contains
                        legal separator characters (comma,
                        space, and/or tab) then the up-arrow
                        (_^) construct must delimit the string.
                        
                range   represents the block of code to be
                        repeated once for each occurrence of
                        a real argument in the list.  The
                        range may contain other macro
                        definitions, repeat ranges and/or
                        the .mexit directive.
        
                .endm   indicates the end of the indefinite
                        repeat block range.

        The .irpc directive is available to permit single character sub-
        stition.  On each iteration of the indefinite repeat range,  the
        dummy  argument  is  replaced  with successive characters in the
        specified string.  


        THE MACRO PROCESSOR                                    PAGE 2-18
        INDEFINITE REPEAT BLOCK DIRECTIVES


        2.6  REPEAT BLOCK DIRECTIVE 


           A repeat block is similar to a macro definition with only one
        argument.  The argument specifies the number of times the repeat
        block  is  inserted  into the assembly stream.  Since the repeat
        directive and its associated range are coded in-line within  the
        source program, this type of macro definition and expansion does
        not require calling the macro by name, as required in the expan-
        sion of the conventional macros previously described.  

           A repeat block can appear within or outside another macro de-
        finition, indefinite repeat block, or repeat block.  


        2.6.1  .rept 


        Format:
        
            [label:]    .rept   exp
                        .
                        .
                    (range of repeat block)
                        .
                        .
                        .endm                   
        
        where:  label   represents an optional statement label.
        
                exp     represents any legal expression.
                        This value controls the number of
                        times the block of code is to be assembled
                        within the program.  When the expression
                        value is less than or equal to zero (0),
                        the repeat block is not assembled.  If
                        this value is not an absolute value, the
                        .rept directive is flagged with an 'r'
                        error.
                        
                range   represents the block of code to be
                        repeated. The range may contain other
                        macro definitions, repeat ranges and/or
                        the .mexit directive.
        
                .endm   indicates the end of the repeat block
                        range.

        The .rept directive is used to duplicate a block of code, a cer-
        tain number of times, in line with other source code.  


        THE MACRO PROCESSOR                                    PAGE 2-19
        REPEAT BLOCK DIRECTIVE


        2.7  MACRO DELETION DIRECTIVE 


           The  .mdelete  directive  deletes  the definitions of the the
        specified macro(s).  


        2.7.1  .mdelete 


        Format:
        
                .mdelete        name1,name2,...,namen
        
        where:  name1,  represent legal macro names. When multiple
                name2,  names are specified, they are separated
                ...,    by any legal separator (comma, space, and/or
                namen   tab).



        2.8  MACRO INVOCATION DETAILS 


           The invocation of a macro, indefinite repeat block, or repeat
        block has specific implications for .if-.else-.endif  constructs
        and for .list-.nlist directives.  

           At  the  point  a  macro,  indefinite repeat block, or repeat
        block is called the following occurs:  

                1)      The initial .if-.else-.endif
                        state is saved.
        
                2)      The initial .list-.nlist
                        state is saved.
        
                3)      The macro, indefinite repeat block,
                        or repeat block is inserted into the
                        assembler source code stream.  All
                        argument substitution is performed
                        at this point.

        When  the  macro  completes and after each pass through an inde-
        finite repeat block or repeat  block  the  .if-.else-.endif  and
        .list-.nlist state is reset to the initial state.  

           The  reset of the .if-.else-.endif state means that the invo-
        cation of a macro, indefinite repeat block, or repeat block can-
        not  change the .if-.else-.endif state of the calling code.  For
        example the following code does not change the  .if-.else-.endif
        condition at macro completion:  


        THE MACRO PROCESSOR                                    PAGE 2-20
        MACRO INVOCATION DETAILS



        
                .macro  fnc     A
                  .if nb,^!A!
                    ...
                    .list (meb)
                    .mexit
                  .else
                    ...
                    .nlist
                    .mexit
                  .endif
                .endm
        
        code:   fnc


           Within the macro the .if condition becomes false but the con-
        dition is not propagated outside the macro.  

           Similarly,  when  the  .list-.nlist state is changed within a
        macro the change is not propogated outside the macro.  

           The  normal  .if-.else-.endif  processing verifies that every
        .if has a corresponding .endif.  When a macro, indefinite repeat
        block,  or repeat block terminates by using the .mexit directive
        the .if-.endif checking is bypassed  because  all  source  lines
        between the .mexit and .endm directives are skipped.  


        2.9  BUILDING A MACRO LIBRARY 


           Using  the macro facilities of the ASxxxx assemblers a simple
        macro library can be built.  The macro library is built by  com-
        bining individual macros, sets of macros, or include file direc-
        tives into a single file.  Each macro entity is enclosed  within
        a .if/.endif block that selects the desired macro definitions.  

           The  selection of specific macros to be imported in a program
        is performed by three macros, .mlib, .mcall,  and  .mload,  con-
        tained in the file mlib.def.  


        THE MACRO PROCESSOR                                    PAGE 2-21
        BUILDING A MACRO LIBRARY


        2.9.1  .mlib Macro Directive 


        Format:
        
                .mlib   file
        
        where:  file    represents the macro library file name.
                        If the file name does not include a path
                        then the path of the current assembly
                        file is used.  If the file name (and/or
                        path) contains white space then the
                        path/name must be delimited with the
                        up-arrow (^) construct ^/    /.

        The .mlib directive defines two macros, .mcall and .mload, which
        when invoked will read a file, importing specific macro  defini-
        tions.   Any  previous  .mcall  and/or .mload directives will be
        deleted before the new .mcall and .mload directives are defined. 

           The  .mload  directive  is an internal directive which simply
        includes the macro library file with the listing disabled.  

           The  following  is the mlib.def file which defines the macros
        .mlib, .mcall, and .mload.  



        THE MACRO PROCESSOR                                    PAGE 2-22
        BUILDING A MACRO LIBRARY


        ;************************************************
        ;*                                              *
        ;*    A simple Macro Library Implementation     *
        ;*                                              *
        ;*              December 2008                   *
        ;*                                              *
        ;************************************************
        
        .macro .mlib    FileName
          .if b,^!FileName!
            .error 1    ; File Name Required
            .mexit
          .endif
          .mdelete      .mcall
          .macro        .mcall  a,b,c,d,e,f,g,h
            .irp sym    ^!a!,^!b!,^!c!,^!d!,^!e!,^!f!,^!g!,^!h!
              .iif nb,^!sym!    .define    .$$.'sym
            .endm
            .mload
            .irp sym    ^!a!,^!b!,^!c!,^!d!,^!e!,^!f!,^!g!,^!h!
              .if nb,^!sym!
                .iif ndef,sym'.$$.    .error  1  ; macro not found
                .undefine       .$$.'sym
                .undefine       sym'.$$.
              .endif
            .endm
          .endm ;.mcall
          .mdelete      .mload
          .macro        .mload
            .nlist
            .include ^!FileName!
            .list
          .endm ;.mload
        .endm   ;.mlib


        2.9.2  .mcall Macro Directive 


        Format:
        
                .mcall  macro1,macro2,...,macro8
        
        where:
        
                macro1, represents from 1 to 8 macro library
                macro2, references to a macro definition or
                ...,    set of macro definitions included in
                macro8  the file specified with the .mlib macro.

        As  can  be  seen  from the macro definition of .mlib and .mcall
        shown above,  when  .mcall  is  invoked  temporary  symbols  are


        THE MACRO PROCESSOR                                    PAGE 2-23
        BUILDING A MACRO LIBRARY


        defined for each macro or macro set that is to be imported.  The
        macro .mload is then invoked to  load  the  macro  library  file
        specified in the call to .mlib.  

           For example, when the following macros are invoked:  

                .mlib   crossasm.sml    ; Cross Assembler Macros
                .mcall  M6809           ; M6809 Macro Group

        The  .mlib  macro  defines the .mload macro to access the system
        macro file crossasm.sml.  Invoking the .mcall  macro  creates  a
        temporary symbol, '.$$.M6809', and then invokes the macro .mload
        to import the system macro file crossasm.sml.   The  file  cros-
        sasm.sml  contains  conditional  statements  that define the re-
        quired macros and creates  a  temporary  symbol  'M6809.$$.'  to
        indicate  the  macro group was found.  If the macro is not found
        an error message is generated.  

           The  following  is a small portion of the crossasm.sml system
        macro file which shows the M6809 macro group:  

                .title  Cross Assembler Macro Library
        
                ; This MACRO Library is Case Insensitive.
                ;
        
                ...
        
        ; Macro Based 6809 Cross Assembler
        
        .$.SML.$. =: 0
        .if     idn     a,A
          .iif  def,.$$.m6809   .$.SML.$. = -1
        .else
          .iif  def,.$$.m6809   .$.SML.$. = -1
          .iif  def,.$$.M6809   .$.SML.$. =  1
        .endif
        .iif    lt,.$.SML.$.    .define         m6809.$$.
        .iif    gt,.$.SML.$.    .define         M6809.$$.
        .iif    ne,.$.SML.$.    .include        "m6809.mac"
        
                ...
        




        THE MACRO PROCESSOR                                    PAGE 2-24
        EXAMPLE MACRO CROSS ASSEMBLERS


        2.10  EXAMPLE MACRO CROSS ASSEMBLERS 


           The  'ascheck'  subdirectory 'macroasm' contains 7 assemblers
        written using only the general macro processing facility of  the
        ASxxxx assemblers:  

                i8085.mac       -  8085 Microprocessor
                m6800.mac       -  6800 Microprocessor
                m6801.mac       -  6801 Microprocessor
                m6804.mac       -  6804 Microprocessor
                m6805.mac       -  6805 Microprocessor
                m6809.mac       -  6809 Microprocessor
                s2650.mac       -  2650 Microprocessor


           These  absolute  macro  cross  assemblers are included to il-
        lustrate the  functionality  of  the  general  macro  processing
        facility  of  the ASxxxx assemblers.  In general they are useful
        examples of actual macro implementations.  














                                    CHAPTER 3

                                   THE LINKER





        3.1  ASLINK RELOCATING LINKER 


           ASLINK is the companion linker for the ASxxxx assemblers.

           The  program ASLINK is a general relocating linker performing
        the following functions:

             1.  Bind multiple object modules into a single memory image

             2.  Resolve inter-module symbol references

             3.  Combine  code  belonging to the same area from multiple
                 object files into a single contiguous memory region

             4.  Search and import object module libraries for undefined
                 global variables

             5.  Perform   byte   and   word  program  counter  relative
                 (pc or pcr) addressing calculations

             6.  Define absolute symbol values at link time

             7.  Define absolute area base address values at link time

             8.  Produce Intel Hex or Motorola S19 output file

             9.  Produce a map of the linked memory image

            10.  Produce  an updated listing file with the relocated ad-
                 dresses and data


        THE LINKER                                              PAGE 3-2
        INVOKING ASLINK


        3.2  INVOKING ASLINK 


           Starting  ASlink without any arguments provides the following
        option list and then exits:  

        Usage: [-Options] [-Option with arg] file
        Usage: [-Options] [-Option with arg] outfile file [file ...]
          -p   Echo commands to stdout (default)
          -n   No echo of commands to stdout
        Alternates to Command Line Input:
          -c                   ASlink >> prompt input
          -f   file[.lnk]      Command File input
        Librarys:
          -k   Library path specification, one per -k
          -l   Library file specification, one per -l
        Relocation:
          -b   area base address=expression
          -g   global symbol=expression
        Map format:
          -m   Map output generated as (out)file[.map]
          -w   Wide listing format for map file
          -x   Hexadecimal (default)
          -d   Decimal
          -q   Octal
        Output:
          -i   Intel Hex as (out)file[.i--]
          -s   Motorola S Record as (out)file[.s--]
          -j   NoICE Debug output as (out)file[.noi]
          -y   SDCDB Debug output as (out)file[.cdb]
          -o   Linked file/library object output enable (default)
          -v   Linked file/library object output disable
        List:
          -u   Update listing file(s) with link data as file(s)[.rst]
        Case Sensitivity:
          -z   Disable Case Sensitivity for Symbols
        End:
          -e   or null line terminates input




                                      NOTE

             When  ASlink  is  invoked  with  a single filename the
             created output file will have the same filename as the
             .rel file.  

             When  ASlink  is  invoked  with multiple filenames the
             first filename is the output filename and the  remain-
             ing  filenames  are  linked  together  into the output


        THE LINKER                                              PAGE 3-3
        INVOKING ASLINK


             filename.  




        Most  sytems  require  the  options to be entered on the command
        line:  

          aslink [-Options] [-Options with args] file

          aslink [-Options] [-Options with args] outfile file1 [file2
        ...]


        Some  systems  may  request  the  arguments  after the linker is
        started at a system specific prompt:  

          aslink
          argv: -[options] -[option arg] file

          aslink
          argv: [-Options] [-Options with args] outfile file1 [file2
        ...]


        The linker commands are explained in some more detail:  

             1.  -c        ASlink >> prompt mode.  
                 The  ASlink >>  prompt  mode reads linker commands from
                 stdin.  

             2.  -f file   Command file mode.  
                 The  command file mode imports linker commands from the
                 specified file (extension must be  .lnk),  imported  -c
                 and  -f  commands  are ignored.  If the directory path,
                 for a file to be linked, is not specified in  the  com-
                 mand  file  then  the  path  defaults  to the .lnk file
                 directory path.  

             3.  -p/-n     enable/disable echoing commands to stdout.  

             4.  -i/-s  Intel  Hex (file.i--), or Motorola S (file.s--)
                 image output file.  

             5.  -o/-v     Specifies      that     subsequent     linked
                 files/libraries will generate object  output  (default)
                 or  suppress  object  output.  (if option -i, -s, or -t
                 was specified) 

             6.  -z        Disable Case Sensitivity for Symbols 



        THE LINKER                                              PAGE 3-4
        INVOKING ASLINK


             7.  -m        Generate  a  map  file (file.map).  This file
                 contains a list of the symbols (by area) with  absolute
                 addresses, sizes of linked areas, and other linking in-
                 formation.  

             8.  -w        Specifies  that a wide listing format be used
                 for the map file.  

             9.  -xdq      Specifies  the  number radix for the map file
                 (Hexadecimal, Decimal, or Octal).  

            10.  -u        Generate  an  updated listing file (file.rst)
                 derived from the relocated addresses and data from  the
                 linker.  

            11.  file      File(s)  to  be  linked.  Files may be on the
                 same line as the above options or on a separate line(s)
                 one file per line or multiple files separated by spaces
                 or tabs.  

            12.  -b  area=expression 
                 (one definition per line in a linker command file.) 
                 This  specifies  an area base address where the expres-
                 sion may contain constants and/or defined symbols  from
                 the linked files.  

            13.  -g  symbol=expression 
                 (one definition per line in a linker command file.) 
                 This  specifies  the value for the symbol where the ex-
                 pression may contain constants and/or  defined  symbols
                 from the linked files.  

            14.  -k  library directory path 
                 (one definition per line in a linker command file.) 
                 This  specifies one possible path to an object library.
                 More than one path is allowed.  

            15.  -l  library file specification 
                 (one definition per line in a linker command file.) 
                 This  specifies a possible library file.  More than one
                 file is allowed.  

            16.  -e  or null line, terminates input to the linker.  

        ASLINK linker supported by and distributed with SDCC are:
                sdld

        sdld specific options:

        Miscellaneous:
          -I   [iram-size] Check for internal RAM overflow
          -X   [xram-size] Check for external RAM overflow
          -C   [code-size] Check for code overflow
          -M   Generate memory usage summary file[mem]
          -Y   Pack internal ram
          -S   [stack-size] Allocate space for stack
          -E   ELF executable as file[elf]

        THE LINKER                                              PAGE 3-5
        LIBRARY PATH(S) AND FILE(S)


        3.3  LIBRARY PATH(S) AND FILE(S) 


           The process of resolving undefined symbols after scanning the
        input object  files  includes  the  scanning  of  object  module
        libraries.   The  linker will search through all combinations of
        the library path specifications (input by the -k option) and the
        library  file  specifications (input by the -l option) that lead
        to an existing library file.  Each library file contains a  list
        (one  file  per  line)  of  modules  included in this particular
        library.  Each existing object module is scanned for a match  to
        the undefined symbol.  The first module containing the symbol is
        then linked with the previous modules to resolve the symbol  de-
        finition.   The  library  object  modules are rescanned until no
        more symbols can be resolved.   The  scanning  algorithm  allows
        resolution  of  back references.  No errors are reported for non
        existant library files or object modules.

           The  library  file  specification may be formed in one of two
        ways:

             1.  If  the  library  file  contained an absolute path/file
                 specification  then  this  is   the   object   module's
                 path/file.
                 (i.e.  C:\...  or C:/...) 

             2.  If  the  library  file  contains  a  relative path/file
                 specification then the concatenation of  the  path  and
                 this  file  specification  becomes  the object module's
                 path/file.
                 (i.e.  \...  or /...) 


           As  an example, assume there exists a library file termio.lib
        in the syslib directory specifying the following object modules:

        \6809\io_disk        first object module
        d:\special\io_comm   second object module

        and the following parameters were specified to the linker:

        -k c:\iosystem\    the first path
        -k c:\syslib\      the second path

        -l termio          the first library file
        -l io              the second library file (no such file)

        The  linker  will attempt to use the following object modules to
        resolve any undefined symbols:

        c:\syslib\6809\io_disk.rel     (concatenated path/file)
        d:\special\io_comm.rel         (absolute path/file)


        THE LINKER                                              PAGE 3-6
        LIBRARY PATH(S) AND FILE(S)



        all  other path(s)/file(s) don't exist.  (No errors are reported
        for non existant path(s)/file(s).)


        3.4  ASLINK PROCESSING 


           The  linker  processes  the  files  in  the  order  they  are
        presented.  The first pass through the input files  is  used  to
        define  all  program  areas, the section area sizes, and symbols
        defined or referenced.  Undefined symbols will initiate a search
        of any specified library file(s) and the importing of the module
        containing the symbol definition.  After the first pass  the  -b
        (area  base  address) definitions, if any, are processed and the
        areas linked.

           The  area  linking proceeds by first examining the area types
        ABS, CON, REL, OVR and PAG.  Absolute areas (ABS) from  separate
        object modules are always overlayed and have been assembled at a
        specific address, these are not normally relocated (if a -b com-
        mand  is  used  on an absolute area the area will be relocated).
        Relative areas (normally defined as REL|CON) have a base address
        of  0x0000  as read from the object files, the -b command speci-
        fies the beginning address of the area.  All subsequent relative
        areas  will  be  concatenated  with  proceeding  relative areas.
        Where specific ordering is desired, the first linker input  file
        should  have  the area definitions in the desired order.  At the
        completion of the area linking all area  addresses  and  lengths
        have  been determined.  The areas of type PAG are verified to be
        on a 256 byte boundary and that the length does not  exceed  256
        bytes.  Any errors are noted on stderr and in the map file.

           Next  the  global symbol definitions (-g option), if any, are
        processed.  The symbol definitions have been delayed until  this
        point because the absolute addresses of all internal symbols are
        known and can be used in the expression calculations.

           Before  continuing  with the linking process the symbol table
        is scanned to determine if any symbols have been referenced  but
        not defined.  Undefined symbols are listed on the stderr device.
        if a .module directive was included in the  assembled  file  the
        module  making  the reference to this undefined variable will be
        printed.

           Constants  defined  as global in more than one module will be
        flagged as multiple definitions if their values are not  identi-
        cal.

           After  the  preceeding  processes are complete the linker may
        output a map file (-m option).  This file provides the following
        information:


        THE LINKER                                              PAGE 3-7
        ASLINK PROCESSING


             1.  Global symbol values and label absolute addresses

             2.  Defined areas and there lengths

             3.  Remaining undefined symbols

             4.  List of modules linked

             5.  List of library modules linked

             6.  List of -b and -g definitions




           The final step of the linking process is performed during the
        second pass of the input files.  As the xxx.rel files  are  read
        the code is relocated by substituting the physical addresses for
        the referenced symbols and areas and may be output in  Intel  or
        Motorola  formats.   The  number of files
         linked and symbols defined/referenced is limited by the proces-
        sor space available to build the area/symbol lists.  If the -u
        option is specified then the listing files  (file.lst)  associated
        with  the  relocation files  (file.rel)  are  scanned  and  used  to
        create a new file (file.rst) which has all addresses and data
        relocated to their final values.

           The  -o/-v  options  allow the simple creation of loadable or
        overlay modules.  Loadable and overlay modules normally need  to
        be  linked  with  a  main module(s) to resolve external symbols.
        The -o/-v options can be used to enable object  output  for  the
        loadable  or overlay module(s) and suppress the object code from
        the linked main module(s).  The -o/-v  options  can  be  applied
        repeatedly  to specify a single linked file, groups of files, or
        libraries for object code inclusion or suppression.  


        THE LINKER                                             Page 3-15
        ASXXXX VERSION 3.XX LINKING


        3.6  ASXXXX VERSION 3.XX LINKING 


           The  linkers'  input  object file is an ascii file containing
        the information needed by the linker  to  bind  multiple  object
        modules into a complete loadable memory image.

        The object module contains the following designators:

                [XDQ][HL][234]
                        X       Hexadecimal radix
                        D       Decimal radix
                        Q       Octal radix

                        H       Most significant byte first
                        L       Least significant byte first
        
                        2       16-Bit Addressing
                        3       24-Bit Addressing
                        4       32-Bit Addressing

                H       Header
                M       Module
                A       Area
                S       Symbol
                T       Object code
                R       Relocation information
                P       Paging information


        3.6.1  Object Module Format


           The   first   line   of   an   object   module  contains  the
        [XDQ][HL][234] format specifier  (i.e.   XH2  indicates  a hexa-
        decimal  file  with  most significant byte first and 16-bit ad-
        dressing) for the following designators.  


        3.6.2  Header Line

                H aa areas gg global symbols

           The  header  line  specifies  the number of areas(aa) and the
        number of global symbols(gg) defined or referenced in  this  ob-
        ject module segment.




        THE LINKER                                             PAGE 3-16
        ASXXXX VERSION 3.XX LINKING


        3.6.3  Module Line 

                M name

           The  module  line  specifies  the module name from which this
        header segment was assembled.  The module line will  not  appear
        if the .module directive was not used in the source program.


        3.6.4  Area Line 

                A label size ss flags ff

           The  area  line  defines the area label, the size (ss) of the
        area in bytes, and the area flags (ff).  The area flags  specify
        the ABS, REL, CON, OVR, and PAG parameters:

                OVR/CON  (0x04/0x00 i.e.  bit position 2)

                ABS/REL  (0x08/0x00 i.e.  bit position 3)

                PAG      (0x10 i.e.  bit position 4)


        3.6.5  Symbol Line 

                S name Defnnnn 

                        or

                S name Refnnnn 

           The symbol line defines (Def) or references (Ref) the identi-
        fier name with the value nnnn.  The defined value is relative to
        the  current area base address.  References to constants and ex-
        ternal global symbols will always appear before the  first  area
        definition.  References to external symbols will have a value of
        zero.


        3.6.6  T Line 

                T xx xx nn nn nn nn nn ...

           The  T  line contains the assembled code output by the assem-
        bler with xx xx being the offset address from the  current  area
        base address and nn being the assembled instructions and data in
        byte format.




        THE LINKER                                             PAGE 3-17
        ASXXXX VERSION 3.XX LINKING


        3.6.7  R Line 

                R 0 0 nn nn n1 n2 xx xx ...

           The R line provides the relocation information to the linker.
        The nn nn value is the current area index, i.e.  which area  the
        current  values  were  assembled.  Relocation information is en-
        coded in groups of 4 bytes:

             1.  n1  is  the  relocation mode and object format, for the
                 adhoc extension modes refer to asxxxx.h or aslink.h 
                 1.  bit 0 word(0x00)/byte(0x01)
                 2.  bit 1 relocatable area(0x00)/symbol(0x02)
                 3.  bit 2 normal(0x00)/PC relative(0x04) relocation
                 4.  bit 3  1-byte(0x00)/2-byte(0x08) object format 
                 5.  bit 4 signed(0x00)/unsigned(0x10) byte data
                 6.  bit 5 normal(0x00)/page '0'(0x20) reference
                 7.  bit 6 normal(0x00)/page 'nnn'(0x40) reference
                 8.  bit 7  LSB byte(0x00)/MSB byte(0x80) 

             2.  n2  is  a byte index into the corresponding (i.e.  pre-
                 ceeding) T line data (i.e.  a pointer to the data to be
                 updated  by  the  relocation).   The T line data may be
                 1-byte or  2-byte  byte  data  format  or  2-byte  word
                 format.

             3.  xx xx  is the area/symbol index for the area/symbol be-
                 ing referenced.  the corresponding area/symbol is found
                 in the header area/symbol lists.


        The groups of 4 bytes are repeated for each item requiring relo-
        cation in the preceeding T line.


        3.6.8  P Line 

                P 0 0 nn nn n1 n2 xx xx

           The  P  line provides the paging information to the linker as
        specified by a .setdp directive.  The format of  the  relocation
        information is identical to that of the R line.  The correspond-
        ing T line has the following information:
                T xx xx aa aa bb bb

           Where  aa aa is the area reference number which specifies the
        selected page area and bb bb is the base address  of  the  page.
        bb bb will require relocation processing if the 'n1 n2 xx xx' is
        specified in the P line.  The linker will verify that  the  base
        address is on a 256 byte boundary and that the page length of an
        area defined with the PAG type is not larger than 256 bytes.



        THE LINKER                                             PAGE 3-18
        ASXXXX VERSION 3.XX LINKING


           The  linker  defaults any direct page references to the first
        area defined in the input REL file.  All ASxxxx assemblers  will
        specify the _CODE area first, making this the default page area.


        3.6.9  24-Bit and 32-Bit Addressing 


           When  24-bit  or  32-bit  addressing is specified in the file
        format line [XDQ][HL][234] then the S and T Lines have  modified
        formats:  
                S name Defnnnnnn                        (24-bit)
                S name Refnnnnnn                        (24-bit)
                T xx xx xx nn nn nn nn nn ...           (24-bit)
        
                S name Defnnnnnnnn                      (32-bit)
                S name Refnnnnnnnn                      (32-bit)
                T xx xx xx xx nn nn nn nn nn ...        (32-bit)

           The  multibyte  formats for byte data replace the 2-byte form
        for 16-bit data with 3-byte or 4-byte data for 24-bit or  32-bit
        data  respectively.  The 2nd byte format (also named MSB) always
        uses the second byte of the 2, 3, or 4-byte data.  


        3.6.10  ASlink V3.xx Error Messages 


           The linker provides detailed error messages allowing the pro-
        grammer to quickly find the errant code.   As  the  linker  com-
        pletes  pass 1  over  the  input  file(s)  it  reports  any page
        boundary or page length errors as follows:

        ?ASlink-Warning-Paged Area PAGE0 Boundary Error

        and/or

        ?ASlink-Warning-Paged Area PAGE0 Length Error

        where PAGE0 is the paged area.

           During  Pass  two the linker reads the T, R, and P lines per-
        forming the necessary relocations and  outputting  the  absolute
        code.  Various errors may be reported during this process 


        THE LINKER                                             PAGE 3-19
        ASXXXX VERSION 3.XX LINKING


        The P line processing can produce only one possible error:

        ?ASlink-Warning-Page Definition Boundary Error
                 file        module      pgarea      pgoffset
          PgDef  t6809l      t6809l      PAGE0       0001

        The error message specifies the file and module where the .setdp
        direct was issued and indicates  the  page  area  and  the  page
        offset value determined after relocation.


        The R line processing produces various errors:

        ?ASlink-Warning-Byte PCR relocation error for symbol  bra2
        ?ASlink-Warning-Unsigned Byte error for symbol  two56
        ?ASlink-Warning-Page0 relocation error for symbol  ltwo56
        ?ASlink-Warning-Page Mode relocation error for symbol  two56
        ?ASlink-Warning-Page Mode relocation error
        ?ASlink-Warning-2K Page relocation error
        ?ASlink-Warning-512K Page relocation error

        These  error  messages  also specify the file, module, area, and
        offset within the area of the code referencing (Refby)  and  de-
        fining (Defin) the symbol:  

        ?ASlink-Warning-Unsigned Byte error for symbol  two56
                 file        module      area        offset
          Refby  t6800l      t6800l      DIRECT      0015
          Defin  tconst      tconst      .  .ABS.    0100

        If the symbol is defined in the same module as the reference the
        linker is unable to report the symbol name.  The assembler list-
        ing  file(s) should be examined at the offset from the specified
        area to locate the offending code.  

           The errors are:

             1.  The  byte PCR error is caused by exceeding the pc rela-
                 tive byte branch range.

             2.  The Unsigned byte error indicates an indexing value was
                 negative or larger than 255.

             3.  The  Page0  error is generated if the direct page vari-
                 able is not in the page0 range of 0 to 255.

             4.  The page mode error is generated if the direct variable
                 is not within the current direct page (6809).

             5.  The  2K  Page  relocation  error  is  generated  if the
                 destination is not within the current  2K  page  (8051,
                 DS8xCxxx).  


        THE LINKER                                             PAGE 3-20
        ASXXXX VERSION 3.XX LINKING


             6.  The  512K  Page  relocation  error  is generated if the
                 destination  is  not  within  the  current  512K   page
                 (DS80C390).  



        THE LINKER                                             Page 3-21
        INTEL IHX OUTPUT FORMAT


        3.7  INTEL IHX OUTPUT FORMAT (16-BIT) 

        Record Mark Field    -  This  field  signifies  the  start  of a
                                record, and consists of an  ascii  colon
                                (:).

        Record Length Field  -  This   field   consists   of  two  ascii
                                characters which indicate the number  of
                                data   bytes   in   this   record.   The
                                characters are the result of  converting
                                the  number  of  bytes  in binary to two
                                ascii characters, high digit first.   An
                                End  of  File  record contains two ascii
                                zeros in this field.

        Load Address Field   -  This  field  consists  of the four ascii
                                characters which result from  converting
                                the  the  binary value of the address in
                                which to begin loading this record.  The
                                order is as follows:

                                    High digit of high byte of address.
                                    Low digit of high byte of address.
                                    High digit of low byte of address.
                                    Low digit of low byte of address.

                                In an End of File record this field con-
                                sists of either four ascii zeros or  the
                                program entry address.  

        Record Type Field    -  This  field  identifies the record type,
                                which is either 0 for data records or  1
                                for  an End of File record.  It consists
                                of two ascii characters, with  the  high
                                digit of the record type first, followed
                                by the low digit of the record type.

        Data Field           -  This  field consists of the actual data,
                                converted to two ascii characters,  high
                                digit first.  There are no data bytes in
                                the End of File record.

        Checksum Field       -  The  checksum  field is the 8 bit binary
                                sum of the record length field, the load
                                address  field,  the  record type field,
                                and the data field.  This  sum  is  then
                                negated  (2's  complement) and converted
                                to  two  ascii  characters,  high  digit
                                first.


        THE LINKER                                             Page 3-22
        INTEL I86 OUTPUT FORMAT


        3.8  INTEL I86 OUTPUT FORMAT (24 OR 32-BIT) 

        Record Mark Field    -  This  field  signifies  the  start  of a
                                record, and consists of an  ascii  colon
                                (:).  

        Record Length Field  -  This   field   consists   of  two  ascii
                                characters which indicate the number  of
                                data   bytes   in   this   record.   The
                                characters are the result of  converting
                                the  number  of  bytes  in binary to two
                                ascii characters, high digit first.   An
                                End  of  File  record contains two ascii
                                zeros in this field.  

        Load Address Field   -  This  field  consists  of the four ascii
                                characters which result from  converting
                                the  the  binary value of the address in
                                which to begin loading this record.  The
                                order is as follows:  

                                    High digit of high byte of address. 
                                    Low digit of high byte of address.  
                                    High digit of low byte of address.  
                                    Low digit of low byte of address.  

                                In an End of File record this field con-
                                sists of either four ascii zeros or  the
                                program entry address.  

        Record Type Field    -  This  field  identifies the record type,
                                which is either 0 for  data  records,  1
                                for  an  End  of File record, or 4 for a
                                segment  record.   It  consists  of  two
                                ascii characters, with the high digit of
                                the record type first, followed  by  the
                                low digit of the record type.  

        Data Field           -  This  field consists of the actual data,
                                converted to two ascii characters,  high
                                digit first.  There are no data bytes in
                                the End of File record.  

        Checksum Field       -  The  checksum  field is the 8 bit binary
                                sum of the record length field, the load
                                address  field,  the  record type field,
                                and the data field.  This  sum  is  then
                                negated  (2's  complement) and converted
                                to  two  ascii  characters,  high  digit
                                first.  


        THE LINKER                                             Page 3-23
        MOTOROLA S1-S9 OUTPUT FORMAT


        3.9  MOTORLA S1-S9 OUTPUT FORMAT (16-BIT) 

        Record Type Field    -  This  field  signifies  the  start  of a
                                record and  identifies  the  the  record
                                type as follows:

                                    Ascii S1 - Data Record
                                    Ascii S9 - End of File Record

        Record Length Field  -  This  field  specifies the record length
                                which includes the  address,  data,  and
                                checksum   fields.   The  8  bit  record
                                length value is converted to  two  ascii
                                characters, high digit first.

        Load Address Field   -  This  field  consists  of the four ascii
                                characters which result from  converting
                                the  the  binary value of the address in
                                which to begin loading this record.  The
                                order is as follows:

                                    High digit of high byte of address.
                                    Low digit of high byte of address.
                                    High digit of low byte of address.
                                    Low digit of low byte of address.

                                In an End of File record this field con-
                                sists of either four ascii zeros or  the
                                program entry address.  

        Data Field           -  This  field consists of the actual data,
                                converted to two ascii characters,  high
                                digit first.  There are no data bytes in
                                the End of File record.

        Checksum Field       -  The  checksum  field is the 8 bit binary
                                sum of the record length field, the load
                                address field, and the data field.  This
                                sum is then  complemented  (1's  comple-
                                ment)   and   converted   to  two  ascii
                                characters, high digit first.














                                    CHAPTER 4

                           BUILDING ASXXXX AND ASLINK




           The assemblers and linker have been successfully compiled for
        Linux, DOS, and various flavors of Windows using the Linux  GCC,
        the Cygwin environment, the DJGPP environment, and the graphical
        user   interfaces   and    command    line    environments    of
        MS Visual C++ V6.0,                       MS Visual Studio 2005,
        MS Visual Studio 2010,  Open Watcom V1.7,   Symantec C/C++ V7.2,
        and Turbo C 3.0.  

           Makefiles  for  Linux,  Cygwin,  DJGPP,  project  files and a
        makefile for Turbo C and psuedo makefiles and project files  for
        VC6,  VS2005,  VS2010, Open Watcom and Symantec are available to
        build all the assemblers and the linker.  

           Unpack  the  asxv5pxx.zip  file into an appropriate directory
        using the utility appropriate to your environment.  For  DOS  or
        Windows  the following command line will unpack the distribution
        zip file:  

                pkunzip -d asxv5pxx.zip


        The  distribution  file  has  been  packed with DOS style end of
        lines (CR/LF), and UPPER CASE file names.  The Linux  make  file
        assumes  all  lower  case directories and file names.  For Linux
        the unpacking utility you choose should have an option to  force
        all  lower  case  directories / file names and convert the ascii
        files to local format.  On most systems  the  following  command
        should do the trick:  

                unzip -L -a asxv5pxx.zip

        Some systems may require a -LL option to force all lower case.  

           The  distribution  will  be  unpacked into the base directory
        'asxv5pxx' which will contain source directories for  each  sup-
        ported  processor  (as6800, asz80, ...), the machine independent
        source  (asxxsrc),  the  linker  source   (linksrc),   and   the


        BUILDING ASXXXX AND ASLINK                              Page 4-2
        


        miscellaneous sources (asxxmisc).  Other directories include the
        documentation (asxdoc), test file directory (asxtst),  html  do-
        cumentation  (asxhtml),  NoICE  support  files  (noice), various
        debug monitors that can be assembled with the ASxxxx  assemblers
        (asmasm),  project files for an application that uses the AS6809
        assembler and ASlink linker (project), and the packaging  direc-
        tory (zipper).  


        4.1  BUILDING ASXXXX AND ASLINK WITH LINUX 


           The  Linux  build  directory is /asxv5pxx/asxmak/linux/build.
        The makefile in this directory is compatible with the Linux  GNU
        make and GCC.  The command 

                make clean

        will  remove  all  the  current  executable  files  in directory
        /asxv5pxx/asxmak/linux/exe and all the compiled  object  modules
        from the /asxv5pxx/asxmak/linux/build directory.  

           The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        4.2  BUILDING ASXXXX AND ASLINK UNDER CYGWIN 


           The  Cygwin build directory is \asxv5pxx\asxmak\cygwin\build.
        The makefile in this directory is compatible with the Cygwin GNU
        make and GCC.  The command 

                make clean

        will  remove  all  the  current  executable  files  in directory
        \asxv5pxx\asxmak\cygwin\exe and all the compiled object  modules
        from the \asxv5pxx\asxmak\cygwin\build directory.  The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can  make  a  single  program by invoking make with the specific


        BUILDING ASXXXX AND ASLINK                              PAGE 4-3
        BUILDING ASXXXX AND ASLINK UNDER CYGWIN


        assembler, linker, or utility you wish to build:  

                make aslink


        4.3  BUILDING ASXXXX AND ASLINK WITH DJGPP 


           The  DJGPP  build  directory is \asxv5pxx\asxmak\djgpp\build.
        The makefile in this directory is compatible with the DJGPP  GNU
        make and GCC.  The command 

                make clean

        will  remove  all  the  current  executable  files  in directory
        \asxv5pxx\asxmak\djgpp\exe and all the compiled  object  modules
        from the \asxv5pxx\asxmak\djgpp\build directory.  The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        4.4  BUILDING ASXXXX AND ASLINK WITH BORLAND'S TURBO C++ 3.0 


           The  Borland  product  is  available in the Borland Turbo C++
        Suite which contains C++ Builder 1.0, Turbo C++ 4.5 for  Windows
        and  Turbo C++ 3.0 for DOS.  The DOS IDE will install and run on
        x86 (16 or 32 bit) versions of Windows (not x64 versions).  


        4.4.1  Graphical User Interface 


           Each   ASxxxx   Assembler  has  two  project  specific  files
        (*.dsk and *.prj)     located      in      the      subdirectory
        \asxv5pxx\asxmak\turboc30\build.    You   must  enter  the  .prj
        filename into the Turbo C++ IDE:  enter Options->Directories and
        change  the  include and output directories to match your confi-
        guration.  After these changes have been made you will  be  able
        to compile the selected project.  These changes must be manually
        entered for each project.  




        BUILDING ASXXXX AND ASLINK                              PAGE 4-4
        BUILDING ASXXXX AND ASLINK WITH BORLAND'S TURBO C++ 3.0


        4.4.2  Command Line Interface 


           Before  the  command line interface can be used you must per-
        form the steps outlined in the 'Graphical  User  Interface'  in-
        structions above for each project you wish to build.  

           Open      a      command     prompt     window     in     the
        \asxv5pxx\asxmak\turboc30\build directory.  Assuming the Turbo C
        compiler  has been installed in the default location (C:\TC) the
        file _setpath.bat will set the PATH variable.  If  this  is  not
        the case then the line 

        PATH=C:\TC;C:\TC\BIN;C:\TC\INCLUDE

        must  be changed to match your environment.  The compiled object
        code      modules      will      be      placed      in      the
        \asxv5pxx\asxmak\turboc30\build\  directory  and  the executable
        files will be placed in the \asxv5pxx\asxmak\turboc30\exe direc-
        tory.  



           The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        The Turbo C make utility uses the information in the correspond-
        ing .prj and .dsk files to compile and link the programs.  

           The file _makeall.bat found in the directory can also be used
        to invoke the Turbo C command line compiler.   The  _makeall.bat
        file calls the _setpath.bat file to set the path to the compiler
        directories in the environment variable PATH  and  then  invokes
        'make all'.  




        BUILDING ASXXXX AND ASLINK                              PAGE 4-5
        BUILDING ASXXXX AND ASLINK WITH MS VISUAL C++ 6.0


        4.5  BUILDING ASXXXX AND ASLINK WITH MS VISUAL C++ 6.0 



        4.5.1  Graphical User Interface 


           Each  ASxxxx Assembler has a VC6 project file (*.dsw) located
        in a subdirectory of \asxv5pxx\asxmak\vc6\build.   Simply  enter
        this project filename into the VC6 IDE and build/rebuild the as-
        sembler.  


        4.5.2  Command Line Interface 


           Open      a      command     prompt     window     in     the
        \asxv5pxx\asxmak\vc6\build directory.  The file  make.bat  found
        in the directory can be used to invoke the VC6 command line com-
        piler.  The make.bat file assumes that the Visual  C++  compiler
        has  been installed in the default location.  If this is not the
        case then the line 

        SET MS$DEV="C:\Program Files\Microsoft Visual Studio\
                       Common\MSDev98\Bin\msdev.exe"

        must  be changed to match your environment.  The compiled object
        code      modules      will      be      placed      in      the
        \asxv5pxx\asxmak\vc6\build\as----\release directory and the exe-
        cutable files will be  placed  in  the  \asxv5pxx\asxmak\vc6\exe
        directory.  



           The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        The  VC6  command line compiler uses the information in the cor-
        responding .dsw/.dsp files to compile and link the programs.  

           The  command  'make clean' is not required or valid as a make
        of anything does a complete rebuild of the program.  



        BUILDING ASXXXX AND ASLINK                              PAGE 4-6
        BUILDING ASXXXX AND ASLINK WITH MS VISUAL STUDIO 2005


        4.6  BUILDING ASXXXX AND ASLINK WITH MS VISUAL STUDIO 2005 



        4.6.1  Graphical User Interface 


           Each  ASxxxx  Assembler  has a VS2005 project file (*.vcproj)
        located in a subdirectory of \asxv5pxx\asxmak\vs05\build.   Sim-
        ply  enter  this  project  filename  into  the  VS2005  IDE  and
        build/rebuild the assembler.  


        4.6.2  Command Line Interface 


           Open      a      command     prompt     window     in     the
        \asxv5pxx\asxmak\vs05\build directory.  The file make.bat  found
        in  the  directory can be used to invoke the VS2005 command line
        compiler.  The make.bat file assumes that the  Visual  C++  com-
        piler  has  been  installed in the default location.  If this is
        not the case then the line 

        SET VC$BUILD="C:\Program Files\Microsoft Visual Studio 8\
                         Common\MSDev98\Bin\msdev.exe"

        must  be changed to match your environment.  The compiled object
        code      modules      will      be      placed      in      the
        \asxv5pxx\asxmak\vs05\build\as----\release directory and the ex-
        ecutable files will be placed in  the  \asxv5pxx\asxmak\vs05\exe
        directory.  



           The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        The  VS2005  command  line  compiler uses the information in the
        corresponding .vcproj file to compile and link the programs.  

           The  command  'make clean' is not required or valid as a make
        of anything does a complete rebuild of the program.  



        BUILDING ASXXXX AND ASLINK                              PAGE 4-7
        BUILDING ASXXXX AND ASLINK WITH MS VISUAL STUDIO 2010


        4.7  BUILDING ASXXXX AND ASLINK WITH MS VISUAL STUDIO 2010 



        4.7.1  Graphical User Interface 


           Each  ASxxxx  Assembler has a VS2010 project file (*.vcxproj)
        located in a subdirectory of \asxv5pxx\asxmak\vs10\build.   Sim-
        ply  enter  this  project  filename  into  the  VS2010  IDE  and
        build/rebuild the assembler.  


        4.7.2  Command Line Interface 


           Open      a      command     prompt     window     in     the
        \asxv5pxx\asxmak\vs10\build directory.  The file make.bat  found
        in  the  directory can be used to invoke the VS2010 command line
        compiler.  The make.bat file assumes that the  Visual  C++  com-
        piler  has  been  installed in the default location.  If this is
        not the case then the line 

        call "c:\Program Files (x86)\Microsoft Visual Studio 10.0\
                         VC\bin\vcvars32.bat"

        must  be changed to match your environment.  The compiled object
        code      modules      will      be      placed      in      the
        \asxv5pxx\asxmak\vs10\build\as----\release directory and the ex-
        ecutable files will be placed in  the  \asxv5pxx\asxmak\vs10\exe
        directory.  



           The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        The  VS2010  command  line  compiler uses the information in the
        corresponding .vcxproj file to compile and link the programs.  

           The  command  'make clean' is not required or valid as a make
        of anything does a complete rebuild of the program.  



        BUILDING ASXXXX AND ASLINK                              PAGE 4-8
        BUILDING ASXXXX AND ASLINK WITH OPEN WATCOM V1.9


        4.8  BUILDING ASXXXX AND ASLINK WITH OPEN WATCOM V1.9 



        4.8.1  Graphical User Interface 


           Each ASxxxx Assembler has a set of project files (.prj, .tgt,
        .mk,   .mk1,   and   .lk1)   located   in    the    subdirectory
        \asxv5pxx\asxmak\watcom\build.   You  will have to edit the pro-
        ject files to match your local file locations.  


        4.8.2  Command Line Interface 


           Open      a      command     prompt     window     in     the
        \asxv5pxx\asxmak\watcom\build directory.   Assuming  the  Watcom
        compiler  has been installed in the default location (C:\WATCOM)
        the file _setpath.bat will set the PATH variable.   If  this  is
        not the case then the line 

        PATH=C:\WATCOM\BINNT;C:\WATCOM\BINW

        must  be changed to match your environment.  The compiled object
        code      modules      will      be      placed      in      the
        \asxv5pxx\asxmak\watcom\build\   directory  and  the  executable
        files will be placed in the  \asxv5pxx\asxmak\watcom\exe  direc-
        tory.  



           The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        The  Watcom command line compiler wmake.exe uses the information
        in the corresponding project files to compile and link the  pro-
        grams.  

           The file _makeall.bat found in the directory can also be used
        to invoke the Watcom command line  compiler.   The  _makeall.bat
        file calls the _setpath.bat file to set the path to the compiler


        BUILDING ASXXXX AND ASLINK                              PAGE 4-9
        BUILDING ASXXXX AND ASLINK WITH OPEN WATCOM V1.9


        directories in the environment variable PATH  and  then  invokes
        'make all'.  

           The  command  'make clean' is not required or valid as a make
        of anything does a complete rebuild of the program.  


        4.9  BUILDING ASXXXX AND ASLINK WITH SYMANTEC C/C++ V7.2 


           The  Symantec  product is no longer available but is included
        for historical reasons (the final version, 7.5,  was  introduced
        in  1996).   The  product had an excellent graphical user inter-
        face, built in editor, project manager, and supported  DOS,  Ex-
        tended  DOS  (the  executable  contained a built in DOS extender
        which was rendered unusable in Windows 2000, after service  pack
        2, or in Windows XP), Win95, and Windows NT.  


        4.9.1  Graphical User Interface 


           Each  ASxxxx Assembler has a series of project specific files
        (*.bro, *.def, *.dpd, *.lnk, *.mak, *.opn, and *.prj) located in
        in  the  subdirectory \asxv5pxx\asxmak\symantec\build.  You must
        enter the .prj filename into the Symantec IDE  and  then  select
        Project->Settings->Directories  and  change the include, target,
        and compiler output directories  to  match  your  configuration.
        After  these  changes have been made you will be able to compile
        the selected project.  These changes must  be  manually  entered
        for each project.  


        4.9.2  Command Line Interface 


           Before  the  command line interface can be used you must per-
        form the steps outlined in the 'Graphical  User  Interface'  in-
        structions above for each project you wish to build.  

           Open      a      command     prompt     window     in     the
        \asxv5pxx\asxmak\symantec\build directory.   The  file  make.bat
        found  in  the directory can be used to invoke the Symantec com-
        mand line compiler.  The make.bat file assumes that the path  to
        the  compiler  directories has been set in the environment vari-
        able PATH.  Assuming the Symantec compiler has been installed in
        the  default location (C:\SC) the file _setpath.bat will set the
        PATH variable.  If this is not the case then the line 

        PATH=C:\SC;C:\SC\BIN;C:\SC\INCLUDE;C:\SC\LIB

        must  be changed to match your environment.  The compiled object


        BUILDING ASXXXX AND ASLINK                             PAGE 4-10
        BUILDING ASXXXX AND ASLINK WITH SYMANTEC C/C++ V7.2


        code      modules      will      be      placed      in      the
        \asxv5pxx\asxmak\symantec\build  directory  and  the  executable
        files will be placed in the \asxv5pxx\asxmak\symantec\exe direc-
        tory.  



           The command 

                make all

        will compile and link all the ASxxxx assemblers, the ASlink pro-
        gram, and the utility programs asxscn and asxcnv.  The make file
        can make a single program by invoking make with the specific as-
        sembler, linker, or utility you wish to build:  

                make aslink


        The  Symantec  make utility , smake.exe, uses the information in
        the corresponding .mak files to compile and link the programs.  

           The file _makeall.bat found in the directory can also be used
        to invoke the Symantec command line compiler.  The  _makeall.bat
        file calls the _setpath.bat file to set the path to the compiler
        directories in the environment variable PATH  and  then  invokes
        'make all'.  


        4.10  THE _CLEAN.BAT AND _PREP.BAT FILES 


           Each  of  the  build  directories have two maintenance files:
        _prep.bat and _clean.bat.  The command file  _prep.bat  prepares
        the particular compiler directories for distribution by removing
        all exteraneous files but keeping  the  final  compiled  execut-
        ables.   The  _clean.bat command file performs the same function
        as _prep.bat and removes the compiled executables.  














                                   APPENDIX AK

                             AS68(HC[S])08 ASSEMBLER





        AK.1  PROCESSOR SPECIFIC DIRECTIVES 


           The MC68HC(S)08 processor is a superset of the MC6805 proces-
        sors.  The AS6808 assembler supports the HC08, HCS08, 6805,  and
        HC05 cores.  


        AK.1.1  .hc08 Directive 

        Format:  

                .hc08 

        The .hc08 directive enables processing of only the HC08 specific
        mnemonics.  6805/HC05/HCS08 mnemonics  encountered  without  the
        .hc08 directive will be flagged with an 'o' error.  

           The  .hc08  directive  also  selects the HC08 specific cycles
        count to be output.  


        AK.1.2  .hcs08 Directive 

        Format:  

                .hcs08 

        The  .hcs08  directive  enables processing of the HCS08 specific
        mnemonics.  

           The  .hcs08  directive also selects the HCS08 specific cycles
        count to be output.  




        AS68(HC[S])08 ASSEMBLER                                PAGE AK-2
        PROCESSOR SPECIFIC DIRECTIVES


        AK.1.3  .6805 Directive 

        Format:  

                .6805 

        The  .6805  directive  enables  processing of only the 6805/HC05
        specific mnemonics.  HC08/HCS08  mnemonics  encountered  without
        the .hc08/.hcs08 directives will be flagged with an 'o' error.  

           The  .6805  directive also selects the MC6805 specific cycles
        count to be output.  


        AK.1.4  .hc05 Directive 

        Format:  

                .hc05 

        The  .hc05  directive  enables  processing of only the 6805/HC05
        specific mnemonics.  HC08/HCS08  mnemonics  encountered  without
        the .hc08/.hcs08 directives will be flagged with an 'o' error.  

           The .hc05 directive also selects the MC68HC05/146805 specific
        cycles count to be output.  


        AK.1.5  The .__.CPU.  Variable 


           The value of the pre-defined symbol '.__.CPU.' corresponds to
        the selected processor type.  The default value is 0 which  cor-
        responds  to  the  default  processor type.  The following table
        lists the processor types and associated values for  the  AS6808
        assembler:  

                Processor Type            .__.CPU. Value
                --------------            --------------
                    .hc08                        0
                    .hcs08                       1
                    .6805                        2
                    .hc05                        3


           The  variable  '.__.CPU.'  is by default defined as local and
        will not be output to the created .rel file.  The assembler com-
        mand line options -g or -a will not cause the local symbol to be
        output to the created .rel file.  

           The  assembler  .globl  directive  may  be used to change the
        variable type to global causing its definition to be  output  to


        AS68(HC[S])08 ASSEMBLER                                PAGE AK-3
        PROCESSOR SPECIFIC DIRECTIVES


        the  .rel file.  The inclusion of the definition of the variable
        '.__.CPU.' might be a useful means of validating that seperately
        assembled  files have been compiled for the same processor type.
        The linker will report an error for variables with multiple  non
        equal definitions.  


        AK.2  68HC(S)08 REGISTER SET 

        The  following  is  a  list  of  the 68HC(S)08 registers used by
        AS6808:  

                a       -       8-bit accumulator
                x       -       index register  <H:X>
                s       -       stack pointer


        AK.3  68HC(S)08 INSTRUCTION SET 


           The  following tables list all 68HC(S)08 mnemonics recognized
        by the AS6808 assembler.  The designation []  refers  to  a  re-
        quired  addressing  mode argument.  The following list specifies
        the format for each addressing mode supported by AS6808:  

                #data           immediate data
                                byte or word data

                *dir            direct page addressing
                                (see .setdp directive)
                                0 <= dir <= 255

                ,x              register indexed addressing
                                zero offset

                offset,x        register indexed addressing
                                  0 <= offset <= 255   --- byte mode
                                256 <= offset <= 65535 --- word mode
                                (an externally defined offset uses the
                                 word mode)

                ,x+             register indexed addressing
                                zero offset with post increment

                offset,x+       register indexed addressing
                                unsigned byte offset with post increment

                offset,s        stack pointer indexed addressing
                                  0 <= offset <= 255   --- byte mode
                                256 <= offset <= 65535 --- word mode
                                (an externally defined offset uses the
                                 word mode)


        AS68(HC[S])08 ASSEMBLER                                PAGE AK-4
        68HC(S)08 INSTRUCTION SET



                ext             extended addressing

                label           branch label

        The terms data, dir, offset, and ext may all be expressions.

           Note  that  not all addressing modes are valid with every in-
        struction, refer to  the  68HC(S)08  technical  data  for  valid
        modes.  


        AK.3.1  Control Instructions 

                clc             cli             daa             div
                mul             nop             nsa             psha
                pshh            pshx            pula            pulh
                pulx            rsp             rti             rts
                sec             sei             stop            swi
                tap             tax             tpa             tsx
                txa             txs             wait


        AK.3.2  Bit Manipulation Instructions 

                brset   #data,*dir,label
                brclr   #data,*dir,label

                bset    #data,*dir
                bclr    #data,*dir


        AK.3.3  Branch Instructions 

                bra     label           brn     label
                bhi     label           bls     label
                bcc     label           bcs     label
                bne     label           beq     label
                bhcc    label           bhcs    label
                bpl     label           bmi     label
                bmc     label           bms     label
                bil     label           bih     label
                bsr     label           bge     label
                blt     label           bgt     label
                ble     label


        AS68(HC[S])08 ASSEMBLER                                PAGE AK-5
        68HC(S)08 INSTRUCTION SET


        AK.3.4  Complex Branch Instructions 

                cbeqa   [],label
                cbeqx   [],label
                cbeq    [],label
                dbnza   label
                dbnzx   label
                dbnz    [],label


        AK.3.5  Read-Modify-Write Instructions 

                nega                    negx
                neg     []

                coma                    comx
                com     []

                lsra                    lsrx
                lsr     []

                rora                    rorx
                ror     []

                asra                    asrx
                asr     []

                asla                    aslx
                asl     []

                lsla                    lslx
                lsl     []

                rola                    rolx
                rol     []

                deca                    decx
                dec     []

                inca                    incx
                inc     []

                tsta                    tstx
                tst     []

                clra                    clrx
                clr     []              clrh

                aix     #data

                ais     #data


        AS68(HC[S])08 ASSEMBLER                                PAGE AK-6
        68HC(S)08 INSTRUCTION SET


        AK.3.6  Register\Memory Instructions 

                sub     []              cmp     []
                sbc     []              cpx     []
                and     []              bit     []
                lda     []              sta     []
                eor     []              adc     []
                ora     []              add     []
                ldx     []              stx     []


        AK.3.7  Double Operand Move Instruction 

                mov     [],[]


        AK.3.8  16-Bit <H:X> Index Register Instructions 

                cphx    []
                ldhx    []
                sthx    []


        AK.3.9  Jump and Jump to Subroutine Instructions 

                jmp     []              jsr     []














                                   APPENDIX AR

                                AS8051 ASSEMBLER





        AR.1  ACKNOWLEDGMENT 


           Thanks  to  John  Hartman  for his contribution of the AS8051
        cross assembler.  

                John L. Hartman
                jhartman at compuserve dot com
                noice at noicedebugger dot com


        AR.2  8051 REGISTER SET 

        The following is a list of the 8051 registers used by AS8051:  

                a,b             -       8-bit accumulators
                r0,r1,r2,r3     -       8-bit registers
                r4,r5,r6,r7
                dptr            -       data pointer
                sp              -       stack pointer
                pc              -       program counter
                psw             -       status word
                c               -       carry (bit in status word)


        AS8051 ASSEMBLER                                       PAGE AR-2
        8051 REGISTER SET


        AR.3  8051 INSTRUCTION SET 


           The  following  tables  list all 8051 mnemonics recognized by
        the AS8051 assembler.  The following list specifies  the  format
        for each addressing mode supported by AS8051:  

                #data           immediate data
                                byte or word data
        
                r,r1,r2         register r0,r1,r2,r3,r4,r5,r6, or r7
        
                @r              indirect on register r0 or r1
                @dptr           indirect on data pointer
                @a+dptr         indirect on accumulator
                                plus data pointer
                @a+pc           indirect on accumulator
                                plus program counter
        
                addr            direct memory address
        
                bitaddr         bit address
        
                label           call or jump label

        The terms data, addr, bitaddr, and label may all be expressions. 

           Note  that  not all addressing modes are valid with every in-
        struction.  Refer to the 8051 technical data for valid modes.  


        AR.3.1  Inherent Instructions 

                nop


        AS8051 ASSEMBLER                                       PAGE AR-3
        8051 INSTRUCTION SET


        AR.3.2  Move Instructions 

                mov     a,#data         mov     a,addr
                mov     a,r             mov     a,@r
        
                mov     r,#data         mov     r,addr
                mov     r,a
        
                mov     addr,a          mov     addr,#data
                mov     addr,r          mov     addr,@r
                mov     addr1,addr2     mov     bitaddr,c
        
                mov     @r,#data        mov     @r,addr
                mov     @r,a
        
                mov     c,bitaddr
                mov     dptr,#data
        
                movc    a,@a+dptr       movc    a,@a+pc
                movx    a,@dptr         movx    a,@r
                movx    @dptr,a         movx    @r,a


        AR.3.3  Single Operand Instructions 

                clr     a               clr     c
                clr     bitaddr
                cpl     a               cpl     c
                cpl     bitaddr
                setb    c               setb    bitaddr
        
                da      a               
                rr      a               rrc     a
                rl      a               rlc     a
                swap    a
        
                dec     a               dec     r
                dec     @r
                inc     a               inc     r
                inc     dptr            inc     @r
        
                div     ab              mul     ab
        
                pop     addr            push    addr


        AS8051 ASSEMBLER                                       PAGE AR-4
        8051 INSTRUCTION SET


        AR.3.4  Two Operand Instructions 

                add     a,#data         add     a,addr
                add     a,r             add     a,@r
                addc    a,#data         addc    a,addr
                addc    a,r             addc    a,@r
                subb    a,#data         subb    a,addr
                subb    a,r             subb    a,@r
                orl     a,#data         orl     a,addr
                orl     a,r             orl     a,@r
                orl     addr,a          orl     addr,#data
                orl     c,bitaddr       orl     c,/bitaddr
                anl     a,#data         anl     a,addr
                anl     a,r             anl     a,@r
                anl     addr,a          anl     addr,#data
                anl     c,bitaddr       anl     c,/bitaddr
                xrl     a,#data         xrl     a,addr
                xrl     a,r             xrl     a,@r
                xrl     addr,a          xrl     addr,#data
                xrl     c,bitaddr       xrl     c,/bitaddr
                xch     a,addr          xch     a,r
                xch     a,@r            xchd    a,@r


        AR.3.5  Call and Return Instructions 

                acall   label           lcall   label
                ret                     reti
                in      data
                out     data
                rst     data


        AR.3.6  Jump Instructions 

                ajmp    label
                cjne    a,#data,label   cjne    a,addr,label
                cjne    r,#data,label   cjne    @r,#data,label
                djnz    r,label         djnz    addr,label
                jbc     bitadr,label
                jb      bitadr,label    jnb     bitadr,label
                jc      label           jnc     label
                jz      label           jnz     label
                jmp     @a+dptr
                ljmp    label           sjmp    label


        AS8051 ASSEMBLER                                       PAGE AR-5
        8051 INSTRUCTION SET


        AR.3.7  Predefined Symbols:  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                FC                                          FF
                F8                                          FB
                F4                                          F7
                F0      B                                   F3
                EC                                          EF
                E8                                          EB
                E4                                          E7
                E0      ACC                                 E3
                DC                                          DF
                D8                                          DB
                D4                                          D7
                D0      PSW                                 D3
                CC   [  TL2     TH2                     ]   CF
                C8   [  T2CON           RCAP2L  RCAP2H  ]   CB
                C4                                          C7
                C0                                          C3
                BC                                          BF
                B8      IP                                  BB
                B4                                          B7
                B0      P3                                  B3
                AC                                          AF
                A8      IE                                  AB
                A4                                          A7
                A0      P2                                  A3
                9C                                          9F
                98      SCON    SBUF                        9B
                94                                          97
                90      P1                                  93
                8C      TH0     TH1                         8F
                88      TCON    TMOD    TL0     TL1         8B
                84                              PCON        87
                80      P0      SP      DPL     DPH         83
        
                [...] Indicates Resident in 8052, not 8051
                A is an allowed alternate for ACC.


        AS8051 ASSEMBLER                                       PAGE AR-6
        8051 INSTRUCTION SET


        AR.3.8  Predefined Symbols:  SFR Bit Addresses 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                FC                                          FF
                F8                                          FB
                F4      B.4     B.5     B.6     B.7         F7
                F0      B.0     B.1     B.2     B.3         F3
                EC                                          EF
                E8                                          EB
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
                E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                DC                                          DF
                D8                                          DB
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
                D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                CC   [  T2CON.4 T2CON.5 T2CON.6 T2CON.7 ]   CF
                C8   [  T2CON.0 T2CON.1 T2CON.2 T2CON.3 ]   CB
                C4                                          C7
                C0                                          C3
                BC      IP.4    IP.5    IP.6    IP.7        BF
                B8      IP.0    IP.1    IP.2    IP.3        BB
                B4      P3.4    P3.5    P3.6    P3.7        B7
                B0      P3.0    P3.1    P3.2    P3.3        B3
                AC      IE.4    IE.5    EI.6    IE.7        AF
                A8      IE.0    IE.1    IE.2    IE.3        AB
                A4      P2.4    P2.5    P2.6    P2.7        A7
                A0      P2.0    P2.1    P2.2    P2.3        A3
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F
                98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                94      P1.4    P1.5    P1.6    P1.7        97
                90      P1.0    P1.1    P1.2    P1.3        93
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
                88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                84      P0.4    P0.5    P0.6    P0.7        87
                80      P0.0    P0.1    P0.2    P0.3        83
        
                [...] Indicates Resident in 8052, not 8051
                A is an allowed alternate for ACC.


        AS8051 ASSEMBLER                                       PAGE AR-7
        8051 INSTRUCTION SET


        AR.3.9  Predefined Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                FC                                          FF
                F8                                          FB
                F4                                          F7
                F0                                          F3
                EC                                          EF
                E8                                          EB
                E4                                          E7
                E0                                          E3
                DC                                          DF
                D8                                          DB
                D4      RS1     F0      AC      CY          D7
                D0      P               OV      RS0         D3
                CC   [  TLCK    RCLK    EXF2    TF2     ]   CF
                C8   [  CPRL2   CT2     TR2     EXEN2   ]   CB
                C4                                          C7
                C0                                          C3
                BC      PS      PT2                         BF
                B8      PX0     PT0     PX1     PT1         BB
                B4                                          B7
                B0      RXD     TXD     INT0    INT1        B3
                AC      ES      ET2             EA          AF
                A8      EX0     ET0     EX1     ET1         AB
                A4                                          A7
                A0                                          A3
                9C      REN     SM2     SM1     SM0         9F
                98      RI      TI      RB8     TB8         9B
                94                                          97
                90                                          93
                8C      TR0     TF0     TR1     TF1         8F
                88      IT0     IE0     IT1     IE1         8B
                84                                          87
                80                                          83
        
                [...] Indicates Resident in 8052, not 8051














                                   APPENDIX AT

                               AS8XCXXX ASSEMBLER





        AT.1  ACKNOWLEDGMENTS 


           Thanks to Bill McKinnon for his contributions to the AS8XCXXX
        cross assembler.  

                Bill McKinnon
                w_mckinnon at conknet dot com

           This  assembler  was  derived from the AS8051 cross assembler
        contributed by John Hartman.  

                John L. Hartman
                jhartman at compuserve dot com
                noice at noicedebugger dot com


        AT.2  AS8XCXXX ASSEMBLER DIRECTIVES 



        AT.2.1  Processor Selection Directives 


           The  AS8XCXXX  assembler  contains  directives to specify the
        processor core SFR (Special Function Registers) and  enable  the
        SFR  Bit  Register values during the assembly process.  The fol-
        lowing directives are supported:  

                .DS8XCXXX               ;80C32 core
                .DS80C310               ;Dallas Semiconductor
                .DS80C320               ;Microprocessors
                .DS80C323
                .DS80C390
                .DS83C520
                .DS83C530


        AS8XCXXX ASSEMBLER                                     PAGE AT-2
        AS8XCXXX ASSEMBLER DIRECTIVES


                .DS83C550
                .DS87C520
                .DS87C530
                .DS87C550

        The invocation of one of the processor directives creates a pro-
        cessor specific symbol and an SFR-Bits symbol.  For example  the
        directive 

                .DS80C390

        creates  the  global  symbols '__DS80C390' and '__SFR_BITS' each
        with a value of 1.  If the microprocessor core selection  direc-
        tive  is  followed  by  an  optional  argument  then  the symbol
        '__SFR_BITS' is given the  value  of  the  argument.   The  file
        DS8XCXXX.SFR  contains  the  SFR and SFR register bit values for
        all the microprocessor selector directives.  This  file  may  be
        modified to create a new SFR for other microprocessor types.  

           If a microprocessor selection directive is not specified then
        no processor symbols will be defined.  This mode allows the  SFR
        and SFR register bit values to be defined by the assembly source
        file.  


        AT.2.2  .cpu Directive 


           The  .cpu  directive  is  similar  to the processor selection
        directives.  This directive defines a  new  processor  type  and
        creates a user defined symbol:  

                .cpu    "CP84C331"      2

           creates  the  symbol  '__CP84C331'  with a value of 1 and the
        symbol '__SFR_BITS' with a value of 2.  These values can be used
        to  select  the  processor SFR and SFR register bits from an in-
        clude file.  If the optional final argument, 2, is omitted  then
        the value of the symbol '__SFR_BITS' is 1.  




        AS8XCXXX ASSEMBLER                                     PAGE AT-3
        AS8XCXXX ASSEMBLER DIRECTIVES


        AT.2.3  Processor Addressing Range Directives 


           If one of the .DS8...  microprocessor selection directives is
        not specified then the following address range assembler  direc-
        tives are accepted:  

                .16bit                  ;16-Bit Addressing
                .24bit                  ;24-Bit Addressing
                .32bit                  ;32-Bit Addressing

        These  directives specify the assembler addressing space and ef-
        fect the output format for the .lst, .sym, and .rel files.  

           The  default  addressing space for defined microprocessors is
        16-Bit except for the DS80C390 microprocessor which is 24-Bit.  

           The  .cpu  directive  defaults to the 16-Bit addressing range
        but this can be changed using these directives.  


        AT.2.4  The .__.CPU.  Variable 


           The value of the pre-defined symbol '.__.CPU.' corresponds to
        the selected processor type.  The default value is 0 which  cor-
        responds  to  the  default  processor type.  The following table
        lists the processor types and associated values for the AS8XCXXX
        assembler:  

                Processor Type            .__.CPU. Value
                --------------            --------------
                  .cpu                           0
        
                  .DS8XCXXX                      1
                  .DS80C310                      2
                  .DS80C320                      3
                  .DS80C323                      4
                  .DS80C390                      5
                  .DS83C520                      6
                  .DS83C530                      7
                  .DS83C550                      8
                  .DS87C520                      9
                  .DS87C530                     10
                  .DS87C550                     11


           The  variable  '.__.CPU.'  is by default defined as local and
        will not be output to the created .rel file.  The assembler com-
        mand line options -g or -a will not cause the local symbol to be
        output to the created .rel file.  



        AS8XCXXX ASSEMBLER                                     PAGE AT-4
        AS8XCXXX ASSEMBLER DIRECTIVES


           The  assembler  .globl  directive  may  be used to change the
        variable type to global causing its definition to be  output  to
        the  .rel file.  The inclusion of the definition of the variable
        '.__.CPU.' might be a useful means of validating that seperately
        assembled  files have been compiled for the same processor type.
        The linker will report an error for variables with multiple  non
        equal definitions.  


        AT.2.5  DS80C390 Addressing Mode Directive 


           The  DS80C390  microprocessor  supports 16-Bit and 24-Bit ad-
        dressing modes.   The  .amode  assembler  directive  provides  a
        method  to  select  the addressing mode used by the ajmp, acall,
        ljmp, and lcall instructions.  These four  instructions  support
        16  and  24 bit addressing modes selected by bits AM0 and AM1 in
        the ACON register.  The assembler is 'informed'  about  the  ad-
        dressing mode selected by using the .amode directive:  

                .amode  2       ;mode 2 is 24-bit addressing

        If  a  second  argument  is specified and its value is non-zero,
        then a three instruction sequence is inserted at the .amode  lo-
        cation loading the mode bits into the ACON register:  

                .amode  2,1     ;mode 2 is 24-bit addressing, load ACON
                ;mov    ta,#0xAA
                ;mov    ta,#0x55
                ;mov    acon,#amode



        AT.2.6  The .msb Directive 


           The .msb directive is available in the AS8XCXXX assembler.  

           The  assembler operator '>' selects the upper byte (MSB) when
        included in an assembler  instruction.   The  default  assembler
        mode  is  to  select bits <15:8> as the MSB.  The .msb directive
        allows the programmer to specify a particular byte as the  'MSB'
        when the address space is larger than 16-bits.  

           The assembler directive   .msb n  configures the assembler to
        select a particular byte as MSB.  Given a 24-bit address of  Nmn
        (N(2) is <23:16>, m(1) is <15:8>, and n(0) is <7:0>) the follow-
        ing examples show how to select a particular address byte:  

                .msb 1          ;select byte 1 of address
                                ;<M(3):N(2):m(1):n(0)>
                LD A,>MNmn      ;byte m <15:8> ==>> A


        AS8XCXXX ASSEMBLER                                     PAGE AT-5
        AS8XCXXX ASSEMBLER DIRECTIVES


                ...
        
                .msb 2          ;select byte 2 of address
                                ;<M(3):N(2):m(1):n(0)>
                LD A,>MNmn      ;byte N <23:16> ==>> A
                ...


        AS8XCXXX ASSEMBLER                                     PAGE AT-6
        AS8XCXXX ASSEMBLER DIRECTIVES


        AT.3  DS8XCXXX REGISTER SET 

        The  AS8XCXXX  cross assembler supports the Dallas Semiconductor
        DS8XCXXX series of 8051-compatible devices.  These  microproces-
        sors  retain  instruction set and object code compatability with
        the 8051 microprocessor.  The DS8XCXXX family  is  updated  with
        several   new  peripherals  while  providing  all  the  standard
        features of the 80C32 microprocessor.  

           The following is a list of the registers used by AS8XCXXX:  

                a,b             -       8-bit accumulators
                r0,r1,r2,r3     -       8-bit registers
                r4,r5,r6,r7
                dptr            -       data pointer
                sp              -       stack pointer
                pc              -       program counter
                psw             -       status word
                c               -       carry (bit in status word)


        AT.4  DS8XCXXX INSTRUCTION SET 


           The  following  tables list all DS8XCXXX mnemonics recognized
        by the AS8XCXXX assembler.  The  following  list  specifies  the
        format for each addressing mode supported by AS8XCXXX:  

                #data           immediate data
                                byte or word data
        
                r,r1,r2         register r0,r1,r2,r3,r4,r5,r6, or r7
        
                @r              indirect on register r0 or r1
                @dptr           indirect on data pointer
                @a+dptr         indirect on accumulator
                                plus data pointer
                @a+pc           indirect on accumulator
                                plus program counter
        
                addr            direct memory address
        
                bitaddr         bit address
        
                label           call or jump label

        The terms data, addr, bitaddr, and label may all be expressions. 

           Note  that  not all addressing modes are valid with every in-
        struction.  Refer to  the  DS8XCXXX  technical  data  for  valid
        modes.  


        AS8XCXXX ASSEMBLER                                     PAGE AT-7
        DS8XCXXX INSTRUCTION SET


        AT.4.1  Inherent Instructions 

                nop


        AT.4.2  Move Instructions 

                mov     a,#data         mov     a,addr
                mov     a,r             mov     a,@r
        
                mov     r,#data         mov     r,addr
                mov     r,a
        
                mov     addr,a          mov     addr,#data
                mov     addr,r          mov     addr,@r
                mov     addr1,addr2     mov     bitaddr,c
        
                mov     @r,#data        mov     @r,addr
                mov     @r,a
        
                mov     c,bitaddr
                mov     dptr,#data
        
                movc    a,@a+dptr       movc    a,@a+pc
                movx    a,@dptr         movx    a,@r
                movx    @dptr,a         movx    @r,a


        AT.4.3  Single Operand Instructions 

                clr     a               clr     c
                clr     bitaddr
                cpl     a               cpl     c
                cpl     bitaddr
                setb    c               setb    bitaddr
        
                da      a               
                rr      a               rrc     a
                rl      a               rlc     a
                swap    a
        
                dec     a               dec     r
                dec     @r
                inc     a               inc     r
                inc     dptr            inc     @r
        
                div     ab              mul     ab
        
                pop     addr            push    addr


        AS8XCXXX ASSEMBLER                                     PAGE AT-8
        DS8XCXXX INSTRUCTION SET


        AT.4.4  Two Operand Instructions 

                add     a,#data         add     a,addr
                add     a,r             add     a,@r
                addc    a,#data         addc    a,addr
                addc    a,r             addc    a,@r
                subb    a,#data         subb    a,addr
                subb    a,r             subb    a,@r
                orl     a,#data         orl     a,addr
                orl     a,r             orl     a,@r
                orl     addr,a          orl     addr,#data
                orl     c,bitaddr       orl     c,/bitaddr
                anl     a,#data         anl     a,addr
                anl     a,r             anl     a,@r
                anl     addr,a          anl     addr,#data
                anl     c,bitaddr       anl     c,/bitaddr
                xrl     a,#data         xrl     a,addr
                xrl     a,r             xrl     a,@r
                xrl     addr,a          xrl     addr,#data
                xrl     c,bitaddr       xrl     c,/bitaddr
                xch     a,addr          xch     a,r
                xch     a,@r            xchd    a,@r


        AT.4.5  Call and Return Instructions 

                acall   label           lcall   label
                ret                     reti
                in      data
                out     data
                rst     data


        AT.4.6  Jump Instructions 

                ajmp    label
                cjne    a,#data,label   cjne    a,addr,label
                cjne    r,#data,label   cjne    @r,#data,label
                djnz    r,label         djnz    addr,label
                jbc     bitadr,label
                jb      bitadr,label    jnb     bitadr,label
                jc      label           jnc     label
                jz      label           jnz     label
                jmp     @a+dptr
                ljmp    label           sjmp    label


        AS8XCXXX ASSEMBLER                                     PAGE AT-9
        DS8XCXXX INSTRUCTION SET


        AT.5  DS8XCXXX SPECIAL FUNCTION REGISTERS 


           The  80C32 core Special Function Registers are selected using
        the .DS8XCXXX assembler directive.  


        AT.5.1  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                80              SP      DPL     DPH         83
                84                              PCON        87
                88      TCON    TMOD    TL0     TL1         8B
                8C      TH0     TH1                         8F
                90      P1                                  93
                94                                          97
                98      SCON    SBUF                        9B
                9C                                          9F
                A0      P2                                  A3
                A4                                          A7
                A8      IE      SADDR0                      AB
                AC                                          AF
                B0      P3                                  B3
                B4                                          B7
                B8      IP      SADEN0                      BB
                BC                                          BF
                C0                                          C3
                C4              STATUS                      C7
                C8      T2CON   T2MOD   RCAP2L  RCAP2H      CB
                CC      TL2     TH2                         CF
                D0      PSW                                 D3
                D4                                          D7
                D8                                          DB
                DC                                          DF
                E0      ACC                                 E3
                E4                                          E7
                E8                                          EB
                EC                                          EF
                F0      B                                   F3
                F4                                          F7
                F8                                          FB
                FC                                          FF


        AS8XCXXX ASSEMBLER                                    PAGE AT-10
        DS8XCXXX SPECIAL FUNCTION REGISTERS


        AT.5.2  Bit Addressable Registers:  Generic 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
        P1      90      P1.0    P1.1    P1.2    P1.3        93
                94      P1.4    P1.5    P1.6    P1.7        97
        SCON    98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F
        P2      A0      P2.0    P2.1    P2.2    P2.3        A3
                A4      P2.4    P2.5    P2.6    P2.7        A7
        IE      A8      IE.0    IE.1    IE.2    IE.3        AB
                AC      IE.4    IE.5    EI.6    IE.7        AF
        P3      B0      P3.0    P3.1    P3.2    P3.3        B3
                B4      P3.4    P3.5    P3.6    P3.7        B7
        IP      B8      IP.0    IP.1    IP.2    IP.3        BB
                BC      IP.4    IP.5    IP.6    IP.7        BF
                C0                                          C3
                C4                                          C7
        T2CON   C8      T2CON.0 T2CON.1 T2CON.2 T2CON.3     CB
                CC      T2CON.4 T2CON.5 T2CON.6 T2CON.7     CF
        PSW     D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
                D8                                          DB
                DC                                          DF
        ACC     E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
                E8                                          EB
                EC                                          EF
        B       F0      B.0     B.1     B.2     B.3         F3
                F4      B.4     B.5     B.6     B.7         F7
                F8                                          FB
                FC                                          FF


        AS8XCXXX ASSEMBLER                                    PAGE AT-11
        DS8XCXXX SPECIAL FUNCTION REGISTERS


        AT.5.3  Bit Addressable Registers:  Specific 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      IT0     IE0     IT1     IE1         8B
                8C      TR0     TF0     TR1     TF1         8F
                90                                          93
                94                                          97
        SCON    98      RI      TI      RB8     TB8         9B
                9C      REN     SM2     SM1     SMO         9F
                A0                                          A3
                A4                                          A7
        IE      A8      EX0     ET0     EX1     ET1         AB
                AC      ES0     ET2             EA          AF
                B0                                          B3
                B4                                          B7
        IP      B8      PX0     PT0     PX1     PT1         BB
                BC      PS0     PT2                         BF
                C0                                          C3
                C4                                          C7
        T2CON   C8      CPRL2   CT2     TR2     EXEN2       CB
                CC      TCLK    RCLK    EXF2    TF2         CF
        PSW     D0      P       FL      OV      RS0         D3
                D4      RS1     F0      AC      CY          D7
                D8                                          DB
                DC                                          DF
                E0                                          E3
                E4                                          E7
                E8                                          EB
                EC                                          EF
                F0                                          F3
                F4                                          F7
                F8                                          FB
                FC                                          FF
        
                Alternates:
        
        SCON    98                                          9B
                9C                              FE          9F
        T2CON   C8      CP_RL2  C_T2                        CB
                CC                                          CF


        AS8XCXXX ASSEMBLER                                    PAGE AT-12
        DS8XCXXX SPECIAL FUNCTION REGISTERS


        AT.5.4  Optional Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                        0x80    0x40    0x20    0x10
                        0x08    0x04    0x02    0x10
                        ----    ----    ----    ----
        PCON    0x80    SMOD    SMOD0                       0x10
                0x08    GF1     GF0     STOP    IDLE        0x01
        TMOD    0x80    T1GATE  T1C_T   T1M1    T1M0        0x10
                0x08    T0GATE  T0C_T   T0M1    T0M0        0x01
        STATUS  0x80            HIP     LIP                 0x10
                0x08                                        0x01
        T2MOD   0x80                                        0x10
                0x08                    T2OE    DCEN        0x01


        AS8XCXXX ASSEMBLER                                    PAGE AT-13
        DS8XCXXX SPECIAL FUNCTION REGISTERS


        AT.6  DS80C310 SPECIAL FUNCTION REGISTERS 


           The  DS80C310  Special  Function Registers are selected using
        the .DS80C310 assembler directive.  


        AT.6.1  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                80              SP      DPL     DPH         83
                84      DPL1    DPH1    DPS     PCON        87
                88      TCON    TMOD    TL0     TL1         8B
                8C      TH0     TH1     CKCON               8F
                90      P1      EXIF                        93
                94                                          97
                98      SCON    SBUF                        9B
                9C                                          9F
                A0      P2                                  A3
                A4                                          A7
                A8      IE      SADDR0                      AB
                AC                                          AF
                B0      P3                                  B3
                B4                                          B7
                B8      IP      SADEN0                      BB
                BC                                          BF
                C0                                          C3
                C4              STATUS                      C7
                C8      T2CON   T2MOD   RCAP2L  RCAP2H      CB
                CC      TL2     TH2                         CF
                D0      PSW                                 D3
                D4                                          D7
                D8      WDCON                               DB
                DC                                          DF
                E0      ACC                                 E3
                E4                                          E7
                E8      EIE                                 EB
                EC                                          EF
                F0      B                                   F3
                F4                                          F7
                F8      EIP                                 FB
                FC                                          FF


        AS8XCXXX ASSEMBLER                                    PAGE AT-14
        DS80C310 SPECIAL FUNCTION REGISTERS


        AT.6.2  Bit Addressable Registers:  Generic 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
        P1      90      P1.0    P1.1    P1.2    P1.3        93
                94      P1.4    P1.5    P1.6    P1.7        97
        SCON    98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F
        P2      A0      P2.0    P2.1    P2.2    P2.3        A3
                A4      P2.4    P2.5    P2.6    P2.7        A7
        IE      A8      IE.0    IE.1    IE.2    IE.3        AB
                AC      IE.4    IE.5    EI.6    IE.7        AF
        P3      B0      P3.0    P3.1    P3.2    P3.3        B3
                B4      P3.4    P3.5    P3.6    P3.7        B7
        IP      B8      IP.0    IP.1    IP.2    IP.3        BB
                BC      IP.4    IP.5    IP.6    IP.7        BF
                C0                                          C3
                C4                                          C7
        T2CON   C8      T2CON.0 T2CON.1 T2CON.2 T2CON.3     CB
                CC      T2CON.4 T2CON.5 T2CON.6 T2CON.7     CF
        PSW     D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
        WDCON   D8      WDCON.0 WDCON.1 WDCON.2 WDCON.3     DB
                DC      WDCON.4 WDCON.5 WDCON.6 WDCON.7     DF
        ACC     E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
        EIE     E8      EIE.0   EIE.1   EIE.2   EIE.3       EB
                EC      EIE.4   EIE.5   EIE.6   EIE.7       EF
        B       F0      B.0     B.1     B.2     B.3         F3
                F4      B.4     B.5     B.6     B.7         F7
        EIP     F8      EIP.0   EIP.1   EIP.2   EIP.3       FB
                FC      EIP.4   EIP.5   EIP.6   EIP.7       FF


        AS8XCXXX ASSEMBLER                                    PAGE AT-15
        DS80C310 SPECIAL FUNCTION REGISTERS


        AT.6.3  Bit Addressable Registers:  Specific 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      IT0     IE0     IT1     IE1         8B
                8C      TR0     TF0     TR1     TF1         8F
                90                                          93
                94                                          97
        SCON    98      RI      TI      RB8     TB8         9B
                9C      REN     SM2     SM1     SMO         9F
                A0                                          A3
                A4                                          A7
        IE      A8      EX0     ET0     EX1     ET1         AB
                AC      ES0     ET2             EA          AF
                B0                                          B3
                B4                                          B7
        IP      B8      PX0     PT0     PX1     PT1         BB
                BC      PS0     PT2                         BF
                C0                                          C3
                C4                                          C7
        T2CON   C8      CPRL2   CT2     TR2     EXEN2       CB
                CC      TCLK    RCLK    EXF2    TF2         CF
        PSW     D0      P       FL      OV      RS0         D3
                D4      RS1     F0      AC      CY          D7
        WDCON   D8                                          DB
                DC                      POR                 DF
                E0                                          E3
                E4                                          E7
        EIE     E8      EX2     EX3     EX4     EX5         EB
                EC                                          EF
                F0                                          F3
                F4                                          F7
        EIP     F8      PX2     PX3     PX4     PX5         FB
                FC                                          FF
        
                Alternates:
        
        SCON    98                                          9B
                9C                              FE          9F
        T2CON   C8      CP_RL2  C_T2                        CB
                CC                                          CF


        AS8XCXXX ASSEMBLER                                    PAGE AT-16
        DS80C310 SPECIAL FUNCTION REGISTERS


        AT.6.4  Optional Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                        0x80    0x40    0x20    0x10
                        0x08    0x04    0x02    0x10
                        ----    ----    ----    ----
        DPS     0x80                                        0x10
                0x08                            SEL         0x01
        PCON    0x80    SMOD    SMOD0                       0x10
                0x08    GF1     GF0     STOP    IDLE        0x01
        TMOD    0x80    T1GATE  T1C_T   T1M1    T1M0        0x10
                0x08    T0GATE  T0C_T   T0M1    T0M0        0x01
        CKCON   0x80                    T2M     T1M         0x10
                0x08    T0M     MD2     MD1     MD0         0x01
        EXIF    0x80    IE5     IE4     IE3     IE2         0x10
                0x08                                        0x01
        STATUS  0x80            HIP     LIP                 0x10
                0x08                                        0x01
        T2MOD   0x80                                        0x10
                0x08                    T2OE    DCEN        0x01
        
                Alternates:
        
        PCON    0x80    SMOD_0                              0x10
                0x08                                        0x01


        AS8XCXXX ASSEMBLER                                    PAGE AT-17
        DS80C310 SPECIAL FUNCTION REGISTERS


        AT.7  DS80C320/DS80C323 SPECIAL FUNCTION REGISTERS 


           The DS80C320/DS80C323 Special Function Registers are selected
        using the .DS80C320 or DS80C323 assembler directives.  


        AT.7.1  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                80              SP      DPL     DPH         83
                84      DPL1    DPH1    DPS     PCON        87
                88      TCON    TMOD    TL0     TL1         8B
                8C      TH0     TH1     CKCON               8F
                90      P1      EXIF                        93
                94                                          97
                98      SCON0   SBUF0                       9B
                9C                                          9F
                A0      P2                                  A3
                A4                                          A7
                A8      IE      SADDR0                      AB
                AC                                          AF
                B0      P3                                  B3
                B4                                          B7
                B8      IP      SADEN0                      BB
                BC                                          BF
                C0      SCON1   SBUF1                       C3
                C4              STATUS          TA          C7
                C8      T2CON   T2MOD   RCAP2L  RCAP2H      CB
                CC      TL2     TH2                         CF
                D0      PSW                                 D3
                D4                                          D7
                D8      WDCON                               DB
                DC                                          DF
                E0      ACC                                 E3
                E4                                          E7
                E8      EIE                                 EB
                EC                                          EF
                F0      B                                   F3
                F4                                          F7
                F8      EIP                                 FB
                FC                                          FF
        
                Alternates:
        
                98      SCON    SBUF                        9B


        AS8XCXXX ASSEMBLER                                    PAGE AT-18
        DS80C320/DS80C323 SPECIAL FUNCTION REGISTERS


        AT.7.2  Bit Addressable Registers:  Generic 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
        P1      90      P1.0    P1.1    P1.2    P1.3        93
                94      P1.4    P1.5    P1.6    P1.7        97
        SCON0   98      SCON0.0 SCON0.1 SCON0.2 SCON0.3     9B
                9C      SCON0.4 SCON0.5 SCON0.6 SCON0.7     9F
        P2      A0      P2.0    P2.1    P2.2    P2.3        A3
                A4      P2.4    P2.5    P2.6    P2.7        A7
        IE      A8      IE.0    IE.1    IE.2    IE.3        AB
                AC      IE.4    IE.5    EI.6    IE.7        AF
        P3      B0      P3.0    P3.1    P3.2    P3.3        B3
                B4      P3.4    P3.5    P3.6    P3.7        B7
        IP      B8      IP.0    IP.1    IP.2    IP.3        BB
                BC      IP.4    IP.5    IP.6    IP.7        BF
        SCON1   C0      SCON1.0 SCON1.1 SCON1.2 SCON1.3     C3
                C4      SCON1.4 SCON1.5 SCON1.6 SCON1.7     C7
        T2CON   C8      T2CON.0 T2CON.1 T2CON.2 T2CON.3     CB
                CC      T2CON.4 T2CON.5 T2CON.6 T2CON.7     CF
        PSW     D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
        WDCON   D8      WDCON.0 WDCON.1 WDCON.2 WDCON.3     DB
                DC      WDCON.4 WDCON.5 WDCON.6 WDCON.7     DF
        ACC     E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
        EIE     E8      EIE.0   EIE.1   EIE.2   EIE.3       EB
                EC      EIE.4   EIE.5   EIE.6   EIE.7       EF
        B       F0      B.0     B.1     B.2     B.3         F3
                F4      B.4     B.5     B.6     B.7         F7
        EIP     F8      EIP.0   EIP.1   EIP.2   EIP.3       FB
                FC      EIP.4   EIP.5   EIP.6   EIP.7       FF
        
                        Alternates:
        
        SCON    98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F


        AS8XCXXX ASSEMBLER                                    PAGE AT-19
        DS80C320/DS80C323 SPECIAL FUNCTION REGISTERS


        AT.7.3  Bit Addressable Registers:  Specific 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      IT0     IE0     IT1     IE1         8B
                8C      TR0     TF0     TR1     TF1         8F
                90                                          93
                94                                          97
        SCON0   98      RI_0    TI_0    RB8_0   TB8_0       9B
                9C      REN_0   SM2_0   SM1_0   SMO_0       9F
                A0                                          A3
                A4                                          A7
        IE      A8      EX0     ET0     EX1     ET1         AB
                AC      ES0     ET2             EA          AF
                B0                                          B3
                B4                                          B7
        IP      B8      PX0     PT0     PX1     PT1         BB
                BC      PS0     PT2                         BF
        SCON1   C0      RI_1    TI_1    RB8_1   TB8_1       C3
                C4      REN_1   SM2_1   SM1_1   SMO_1       C7
        T2CON   C8      CPRL2   CT2     TR2     EXEN2       CB
                CC      TCLK    RCLK    EXF2    TF2         CF
        PSW     D0      P       FL      OV      RS0         D3
                D4      RS1     F0      AC      CY          D7
        WDCON   D8      RWT     EWT     WTRF    WDIF        DB
                DC      PFI     EPFI    POR     SMOD_1      DF
                E0                                          E3
                E4                                          E7
        EIE     E8      EX2     EX3     EX4     EX5         EB
                EC      EWDI                                EF
                F0                                          F3
                F4                                          F7
        EIP     F8      PX2     PX3     PX4     PX5         FB
                FC      PWDI                                FF
        
                Alternates:
        
        SCON    98      RI      TI      RB8     TB8         9B
                9C      REN     SM2     SM1     SMO         9F
        SCON    98                                          9B
                9C                              FE          9F
        SCON0   98                                          9B
                9C                              FE_0        9F
        SCON1   C0                                          C3
                C4                              FE_1        C7
        T2CON   C8      CP_RL2  C_T2                        CB
                CC                                          CF


        AS8XCXXX ASSEMBLER                                    PAGE AT-20
        DS80C320/DS80C323 SPECIAL FUNCTION REGISTERS


        AT.7.4  Optional Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                        0x80    0x40    0x20    0x10
                        0x08    0x04    0x02    0x10
                        ----    ----    ----    ----
        DPS     0x80                                        0x10
                0x08                            SEL         0x01
        PCON    0x80    SMOD_0  SMOD0                       0x10
                0x08    GF1     GF0     STOP    IDLE        0x01
        TMOD    0x80    T1GATE  T1C_T   T1M1    T1M0        0x10
                0x08    T0GATE  T0C_T   T0M1    T0M0        0x01
        CKCON   0x80    WD1     WD0     T2M     T1M         0x10
                0x08    T0M     MD2     MD1     MD0         0x01
        EXIF    0x80    IE5     IE4     IE3     IE2         0x10
                0x08            RGMD    RGSL    BGS         0x01
        STATUS  0x80    PIP     HIP     LIP                 0x10
                0x08                                        0x01
        T2MOD   0x80                                        0x10
                0x08                    T2OE    DCEN        0x01
        
                Alternates:
        
        PCON    0x80    SMOD                                0x10
                0x08                                        0x01


        AS8XCXXX ASSEMBLER                                    PAGE AT-21
        DS80C320/DS80C323 SPECIAL FUNCTION REGISTERS


        AT.8  DS80C390 SPECIAL FUNCTION REGISTERS 


           The  DS80C390  Special  Function Registers are selected using
        the .DS80C390 assembler directive.  


        AT.8.1  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                80      P4      SP      DPL     DPH         83
                84      DPL1    DPH1    DPS     PCON        87
                88      TCON    TMOD    TL0     TL1         8B
                8C      TH0     TH1     CKCON               8F
                90      P1      EXIF    P4CNT   DPX         93
                94              DPX1    C0RMS0  C0RMS1      97
                98      SCON0   SBUF0           ESP         9B
                9C      AP      ACON    C0TMA0  C0TMA1      9F
                A0      P2      P5      P5CNT   C0C         A3
                A4      C0S     C0IR    C0TE    C0RE        A7
                A8      IE      SADDR0  SADDR1  C0M1C       AB
                AC      C0M2C   C0M3C   C0M4C   C0M5C       AF
                B0      P3                      C0M6C       B3
                B4      C0M7C   C0M8C   C0M9C   C0M10C      B7
                B8      IP      SADEN0  SADEN1  C0M11C      BB
                BC      C0M12C  C0M13C  C0M14C  C0M15C      BF
                C0      SCON1   SBUF1                       C3
                C4      PMR     STATUS  MCON    TA          C7
                C8      T2CON   T2MOD   RCAP2L  RCAP2H      CB
                CC      TL2     TH2     COR                 CF
                D0      PSW     MCNT0   MCNT1   MA          D3
                D4      MB      MC      C1RMS0  C1RMS1      D7
                D8      WDCON                               DB
                DC                      C1TMA0  C1TMA1      DF
                E0      ACC                     C1C         E3
                E4      C1S     C1IR    C1TE    C1RE        E7
                E8      EIE             MXAX    C1M1C       EB
                EC      C1M2C   C1M3C   C1M4C   C1M5C       EF
                F0      B                       C1M6C       F3
                F4      C1M7C   C1M8C   C1M9C   C1M10C      F7
                F8      EIP                     C1M11C      FB
                FC      C1M12C  C1M13C  C1M14C  C1M15C      FF
        
                Alternates:
        
                98      SCON    SBUF                        9B


        AS8XCXXX ASSEMBLER                                    PAGE AT-22
        DS80C390 SPECIAL FUNCTION REGISTERS


        AT.8.2  Bit Addressable Registers:  Generic 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
        P4      80      P4.0    P4.1    P4.2    P4.3        83
                84      P4.4    P4.5    P4.6    P4.7        87
        TCON    88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
        P1      90      P1.0    P1.1    P1.2    P1.3        93
                94      P1.4    P1.5    P1.6    P1.7        97
        SCON0   98      SCON0.0 SCON0.1 SCON0.2 SCON0.3     9B
                9C      SCON0.4 SCON0.5 SCON0.6 SCON0.7     9F
        P2      A0      P2.0    P2.1    P2.2    P2.3        A3
                A4      P2.4    P2.5    P2.6    P2.7        A7
        IE      A8      IE.0    IE.1    IE.2    IE.3        AB
                AC      IE.4    IE.5    EI.6    IE.7        AF
        P3      B0      P3.0    P3.1    P3.2    P3.3        B3
                B4      P3.4    P3.5    P3.6    P3.7        B7
        IP      B8      IP.0    IP.1    IP.2    IP.3        BB
                BC      IP.4    IP.5    IP.6    IP.7        BF
        SCON1   C0      SCON1.0 SCON1.1 SCON1.2 SCON1.3     C3
                C4      SCON1.4 SCON1.5 SCON1.6 SCON1.7     C7
        T2CON   C8      T2CON.0 T2CON.1 T2CON.2 T2CON.3     CB
                CC      T2CON.4 T2CON.5 T2CON.6 T2CON.7     CF
        PSW     D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
        WDCON   D8      WDCON.0 WDCON.1 WDCON.2 WDCON.3     DB
                DC      WDCON.4 WDCON.5 WDCON.6 WDCON.7     DF
        ACC     E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
        EIE     E8      EIE.0   EIE.1   EIE.2   EIE.3       EB
                EC      EIE.4   EIE.5   EIE.6   EIE.7       EF
        B       F0      B.0     B.1     B.2     B.3         F3
                F4      B.4     B.5     B.6     B.7         F7
        EIP     F8      EIP.0   EIP.1   EIP.2   EIP.3       FB
                FC      EIP.4   EIP.5   EIP.6   EIP.7       FF
        
                        Alternates:
        
        SCON    98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F


        AS8XCXXX ASSEMBLER                                    PAGE AT-23
        DS80C390 SPECIAL FUNCTION REGISTERS


        AT.8.3  Bit Addressable Registers:  Specific 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      IT0     IE0     IT1     IE1         8B
                8C      TR0     TF0     TR1     TF1         8F
        P1      90      T2      T2EX    RXD1    TXD1        93
                94      INT2    INT3    INT4    INT5        97
        SCON0   98      RI_0    TI_0    RB8_0   TB8_0       9B
                9C      REN_0   SM2_0   SM1_0   SMO_0       9F
                A0                                          A3
                A4                                          A7
        IE      A8      EX0     ET0     EX1     ET1         AB
                AC      ES0     ET2     ES1     EA          AF
        P3      B0      RXD0    TXD0    INT0    INT1        B3
                B4      T0      T1                          B7
        IP      B8      PX0     PT0     PX1     PT1         BB
                BC      PS0     PT2     PS1                 BF
        SCON1   C0      RI_1    TI_1    RB8_1   TB8_1       C3
                C4      REN_1   SM2_1   SM1_1   SMO_1       C7
        T2CON   C8      CPRL2   CT2     TR2     EXEN2       CB
                CC      TCLK    RCLK    EXF2    TF2         CF
        PSW     D0      P       FL      OV      RS0         D3
                D4      RS1     F0      AC      CY          D7
        WDCON   D8      RWT     EWT     WTRF    WDIF        DB
                DC      PFI     EPFI    POR     SMOD_1      DF
                E0                                          E3
                E4                                          E7
        EIE     E8      EX2     EX3     EX4     EX5         EB
                EC      EWDI    C1IE    C0IE    CANBIE      EF
                F0                                          F3
                F4                                          F7
        EIP     F8      PX2     PX3     PX4     PX5         FB
                FC      PWDI    C1IP    C0IP    CANBIP      FF
        
                Alternates:
        
        SCON    98      RI      TI      RB8     TB8         9B
                9C      REN     SM2     SM1     SMO         9F
        SCON    98                                          9B
                9C                              FE          9F
        SCON0   98                                          9B
                9C                              FE_0        9F
        SCON1   C0                                          C3
                C4                              FE_1        C7
        T2CON   C8      CP_RL2  C_T2                        CB
                CC                                          CF


        AS8XCXXX ASSEMBLER                                    PAGE AT-24
        DS80C390 SPECIAL FUNCTION REGISTERS


        AT.8.4  Optional Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                        0x80    0x40    0x20    0x10
                        0x08    0x04    0x02    0x10
                        ----    ----    ----    ----
        DPS     0x80    ID1     ID0     TSL                 0x10
                0x08                            SEL         0x01
        PCON    0x80    SMOD_0  SMOD0   OFDF    OFDE        0x10
                0x08    GF1     GF0     STOP    IDLE        0x01
        TMOD    0x80    T1GATE  T1C_T   T1M1    T1M0        0x10
                0x08    T0GATE  T0C_T   T0M1    T0M0        0x01
        CKCON   0x80    WD1     WD0     T2M     T1M         0x10
                0x08    T0M     MD2     MD1     MD0         0x01
        EXIF    0x80    IE5     IE4     IE3     IE2         0x10
                0x08    CKRY    RGMD    RGSL    BGS         0x01
        P4CNT   0x80            SBCAN                       0x10
                0x08                                        0x01
        ESP     0x80                                        0x10
                0x08                    ESP.1   ESP.0       0x01
        ACON    0x80                                        0x10
                0x08            SA      AM1     AM0         0x01
        P5      0x80    P5.7    P5.6    P5.5    P5.4        0x10
                0x08    P5.3    P5.2    P5.1    P5.0        0x01
        P5CNT   0x80    CAN1BA  CAN0BA  SP1EC   C1_IO       0x10
                0x08    C0_IO   P5CNT.2 P5CNT.1 P5CNT.0     0x01
        CxC     0x80    ERIE    STIE    PDE     SIESTA      0x10
                0x08    CRST    AUTOB   ERCS    SWINT       0x01
        CxS     0x80    BSS   EC96_128  WKS     RXS         0x10
                0x08    TXS     ER2     ER1     ER0         0x01
        CxIR    0x80    INTIN7  INTIN6  INTIN5  INTIN4      0x10
                0x08    INTIN3  INTIN2  INTIN1  INTIN0      0x01
        CxCxxC  0x80    MSRDY   ET1     ER1     INTRQ       0x10
                0x08    EXTRQ   MTRQ    ROW_TIH DTUP        0x01
        PMR     0x80    CD1     CD0     SWB     CTM         0x10
                0x08    4X_2X   ALEOFF                      0x01
        STATUS  0x80    PIP     HIP     LIP                 0x10
                0x08    SPTA1   SPRA1   SPTA0   SPRA0       0x01
        MCON    0x80    IDM1    IDM0    CMA                 0x10
                0x08    PDCE3   PDCE2   PDCE1   PDCE0       0x01
        T2MOD   0x80                            D13T1       0x10
                0x08    D13T2           T2OE    DCEN        0x01
        COR     0x80    IRDACK  C1BPR7  C1BPR6  C0BPR7      0x10
                0x08    C0BPR6  COD1    COD0    CLKOE       0x01
        MCNT0   0x80    _LSHIFT CSE     SCB     MAS4        0x10
                0x08    MAS3    MAS2    MAS1    MAS0        0x01
        MCNT1   0x80    MST     MOF             CLM         0x10
                0x08                                        0x01
        
                Alternates:
        


        AS8XCXXX ASSEMBLER                                    PAGE AT-25
        DS80C390 SPECIAL FUNCTION REGISTERS


        PCON    0x80    SMOD                                0x10
                0x08                                        0x01


        AS8XCXXX ASSEMBLER                                    PAGE AT-26
        DS80C390 SPECIAL FUNCTION REGISTERS


        AT.9  DS83C520/DS87C520 SPECIAL FUNCTION REGISTERS 


           The DS83C520/DS87C520 Special Function Registers are selected
        using the .DS83C520 or DS87C520 assembler directives.  


        AT.9.1  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                80      P0      SP      DPL     DPH         83
                84      DPL1    DPH1    DPS     PCON        87
                88      TCON    TMOD    TL0     TL1         8B
                8C      TH0     TH1     CKCON               8F
                90      PORT1   EXIF                        93
                94                                          97
                98      SCON0   SBUF0                       9B
                9C                                          9F
                A0      P2                                  A3
                A4                                          A7
                A8      IE      SADDR0  SADDR1              AB
                AC                                          AF
                B0      P3                                  B3
                B4                                          B7
                B8      IP      SADEN0  SADEN1              BB
                BC                                          BF
                C0      SCON1   SBUF1   ROMSIZE             C3
                C4      PMR     STATUS          TA          C7
                C8      T2CON   T2MOD   RCAP2L  RCAP2H      CB
                CC      TL2     TH2                         CF
                D0      PSW                                 D3
                D4                                          D7
                D8      WDCON                               DB
                DC                                          DF
                E0      ACC                                 E3
                E4                                          E7
                E8      EIE                                 EB
                EC                                          EF
                F0      B                                   F3
                F4                                          F7
                F8      EIP                                 FB
                FC                                          FF
        
                Alternates:
        
                98      SCON    SBUF                        9B


        AS8XCXXX ASSEMBLER                                    PAGE AT-27
        DS83C520/DS87C520 SPECIAL FUNCTION REGISTERS


        AT.9.2  Bit Addressable Registers:  Generic 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
        P0      80      P0.7    P0.6    P0.5    P0.4        83
                84      P0.3    P0.2    P0.1    P0.0        87
        TCON    88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
        PORT1   90      P1.0    P1.1    P1.2    P1.3        93
                94      P1.4    P1.5    P1.6    P1.7        97
        SCON0   98      SCON0.0 SCON0.1 SCON0.2 SCON0.3     9B
                9C      SCON0.4 SCON0.5 SCON0.6 SCON0.7     9F
        P2      A0      P2.0    P2.1    P2.2    P2.3        A3
                A4      P2.4    P2.5    P2.6    P2.7        A7
        IE      A8      IE.0    IE.1    IE.2    IE.3        AB
                AC      IE.4    IE.5    EI.6    IE.7        AF
        P3      B0      P3.0    P3.1    P3.2    P3.3        B3
                B4      P3.4    P3.5    P3.6    P3.7        B7
        IP      B8      IP.0    IP.1    IP.2    IP.3        BB
                BC      IP.4    IP.5    IP.6    IP.7        BF
        SCON1   C0      SCON1.0 SCON1.1 SCON1.2 SCON1.3     C3
                C4      SCON1.4 SCON1.5 SCON1.6 SCON1.7     C7
        T2CON   C8      T2CON.0 T2CON.1 T2CON.2 T2CON.3     CB
                CC      T2CON.4 T2CON.5 T2CON.6 T2CON.7     CF
        PSW     D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
        WDCON   D8      WDCON.0 WDCON.1 WDCON.2 WDCON.3     DB
                DC      WDCON.4 WDCON.5 WDCON.6 WDCON.7     DF
        ACC     E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
        EIE     E8      EIE.0   EIE.1   EIE.2   EIE.3       EB
                EC      EIE.4   EIE.5   EIE.6   EIE.7       EF
        B       F0      B.0     B.1     B.2     B.3         F3
                F4      B.4     B.5     B.6     B.7         F7
        EIP     F8      EIP.0   EIP.1   EIP.2   EIP.3       FB
                FC      EIP.4   EIP.5   EIP.6   EIP.7       FF
        
                        Alternates:
        
        PORT1   90      PORT1.0 PORT1.1 PORT1.2 PORT1.3     93
                94      PORT1.4 PORT1.5 PORT1.6 PORT1.7     97
        SCON    98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F


        AS8XCXXX ASSEMBLER                                    PAGE AT-28
        DS83C520/DS87C520 SPECIAL FUNCTION REGISTERS


        AT.9.3  Bit Addressable Registers:  Specific 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      IT0     IE0     IT1     IE1         8B
                8C      TR0     TF0     TR1     TF1         8F
                90                                          93
                94                                          97
        SCON0   98      RI_0    TI_0    RB8_0   TB8_0       9B
                9C      REN_0   SM2_0   SM1_0   SMO_0       9F
                A0                                          A3
                A4                                          A7
        IE      A8      EX0     ET0     EX1     ET1         AB
                AC      ES0     ET2     ES1     EA          AF
                B0                                          B3
                B4                                          B7
        IP      B8      PX0     PT0     PX1     PT1         BB
                BC      PS0     PT2     PS1                 BF
        SCON1   C0      RI_1    TI_1    RB8_1   TB8_1       C3
                C4      REN_1   SM2_1   SM1_1   SMO_1       C7
        T2CON   C8      CPRL2   CT2     TR2     EXEN2       CB
                CC      TCLK    RCLK    EXF2    TF2         CF
        PSW     D0      P       FL      OV      RS0         D3
                D4      RS1     F0      AC      CY          D7
        WDCON   D8      RWT     EWT     WTRF    WDIF        DB
                DC      PFI     EPFI    POR     SMOD_1      DF
                E0                                          E3
                E4                                          E7
        EIE     E8      EX2     EX3     EX4     EX5         EB
                EC      EWDI                                EF
                F0                                          F3
                F4                                          F7
        EIP     F8      PX2     PX3     PX4     PX5         FB
                FC      PWDI                                FF
        
                Alternates:
        
        SCON    98      RI      TI      RB8     TB8         9B
                9C      REN     SM2     SM1     SMO         9F
        SCON    98                                          9B
                9C                              FE          9F
        SCON0   98                                          9B
                9C                              FE_0        9F
        SCON1   C0                                          C3
                C4                              FE_1        C7
        T2CON   C8      CP_RL2  C_T2                        CB
                CC                                          CF


        AS8XCXXX ASSEMBLER                                    PAGE AT-29
        DS83C520/DS87C520 SPECIAL FUNCTION REGISTERS


        AT.9.4  Optional Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                        0x80    0x40    0x20    0x10
                        0x08    0x04    0x02    0x10
                        ----    ----    ----    ----
        DPS     0x80                                        0x10
                0x08                            SEL         0x01
        PCON    0x80    SMOD_0  SMOD0                       0x10
                0x08    GF1     GF0     STOP    IDLE        0x01
        TMOD    0x80    T1GATE  T1C_T   T1M1    T1M0        0x10
                0x08    T0GATE  T0C_T   T0M1    T0M0        0x01
        CKCON   0x80    WD1     WD0     T2M     T1M         0x10
                0x08    T0M     MD2     MD1     MD0         0x01
        EXIF    0x80    IE5     IE4     IE3     IE          0x10
                0x08    XT_RG   RGMD    RGSL    BGS         0x01
        SBUF1   0x80    SB7     SB6     SB5     SB4         0x10
                0x08    SB3     SB2     SB1     SB0         0x01
        ROMSIZE 0x80                                        0x10
                0x08            RMS2    RMS1    RMS0        0x01
        PMR     0x80    CD1     CD0     SWB                 0x10
                0x08    XTOFF   ALEOFF  DME1    DME0        0x01
        STATUS  0x80    PIP     HIP     LIP     XTUP        0x10
                0x08    SPTA1   SPRA1   SPTA0   SPRA0       0x01
        T2MOD   0x80                                        0x10
                0x08                    T2OE    DCEN        0x01
        
                Alternates:
        
        PCON    0x80    SMOD                                0x10
                0x08                                        0x01


        AS8XCXXX ASSEMBLER                                    PAGE AT-30
        DS83C520/DS87C520 SPECIAL FUNCTION REGISTERS


        AT.10  DS83C530/DS87C530 SPECIAL FUNCTION REGISTERS 


           The DS83C530/DS87C530 Special Function Registers are selected
        using the .DS83C530 or DS87C530 assembler directives.  


        AT.10.1  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                80      P0      SP      DPL     DPH         83
                84      DPL1    DPH1    DPS     PCON        87
                88      TCON    TMOD    TL0     TL1         8B
                8C      TH0     TH1     CKCON               8F
                90      P1      EXIF                        93
                94                      TRIM                97
                98      SCON0   SBUF0                       9B
                9C                                          9F
                A0      P2                                  A3
                A4                                          A7
                A8      IE      SADDR0  SADDR1              AB
                AC                                          AF
                B0      P3                                  B3
                B4                                          B7
                B8      IP      SADEN0  SADEN1              BB
                BC                                          BF
                C0      SCON1   SBUF1   ROMSIZE             C3
                C4      PMR     STATUS          TA          C7
                C8      T2CON   T2MOD   RCAP2L  RCAP2H      CB
                CC      TL2     TH2                         CF
                D0      PSW                                 D3
                D4                                          D7
                D8      WDCON                               DB
                DC                                          DF
                E0      ACC                                 E3
                E4                                          E7
                E8      EIE                                 EB
                EC                                          EF
                F0      B               RTASS   RTAS        F3
                F4      RTAM    RTAH                        F7
                F8      EIP     RTCC    RTCSS   RTCS        FB
                FC      RTCM    RTCH    RTCD0   RTCD1       FF
        
                Alternates:
        
                98      SCON    SBUF                        9B


        AS8XCXXX ASSEMBLER                                    PAGE AT-31
        DS83C530/DS87C530 SPECIAL FUNCTION REGISTERS


        AT.10.2  Bit Addressable Registers:  Generic 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
        P0      80      P0.7    P0.6    P0.5    P0.4        83
                84      P0.3    P0.2    P0.1    P0.0        87
        TCON    88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
        P1      90      P1.0    P1.1    P1.2    P1.3        93
                94      P1.4    P1.5    P1.6    P1.7        97
        SCON0   98      SCON0.0 SCON0.1 SCON0.2 SCON0.3     9B
                9C      SCON0.4 SCON0.5 SCON0.6 SCON0.7     9F
        P2      A0      P2.0    P2.1    P2.2    P2.3        A3
                A4      P2.4    P2.5    P2.6    P2.7        A7
        IE      A8      IE.0    IE.1    IE.2    IE.3        AB
                AC      IE.4    IE.5    EI.6    IE.7        AF
        P3      B0      P3.0    P3.1    P3.2    P3.3        B3
                B4      P3.4    P3.5    P3.6    P3.7        B7
        IP      B8      IP.0    IP.1    IP.2    IP.3        BB
                BC      IP.4    IP.5    IP.6    IP.7        BF
        SCON1   C0      SCON1.0 SCON1.1 SCON1.2 SCON1.3     C3
                C4      SCON1.4 SCON1.5 SCON1.6 SCON1.7     C7
        T2CON   C8      T2CON.0 T2CON.1 T2CON.2 T2CON.3     CB
                CC      T2CON.4 T2CON.5 T2CON.6 T2CON.7     CF
        PSW     D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
        WDCON   D8      WDCON.0 WDCON.1 WDCON.2 WDCON.3     DB
                DC      WDCON.4 WDCON.5 WDCON.6 WDCON.7     DF
        ACC     E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
        EIE     E8      EIE.0   EIE.1   EIE.2   EIE.3       EB
                EC      EIE.4   EIE.5   EIE.6   EIE.7       EF
        B       F0      B.0     B.1     B.2     B.3         F3
                F4      B.4     B.5     B.6     B.7         F7
        EIP     F8      EIP.0   EIP.1   EIP.2   EIP.3       FB
                FC      EIP.4   EIP.5   EIP.6   EIP.7       FF
        
                        Alternates:
        
        SCON    98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F


        AS8XCXXX ASSEMBLER                                    PAGE AT-32
        DS83C530/DS87C530 SPECIAL FUNCTION REGISTERS


        AT.10.3  Bit Addressable Registers:  Specific 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      IT0     IE0     IT1     IE1         8B
                8C      TR0     TF0     TR1     TF1         8F
                90                                          93
                94                                          97
        SCON0   98      RI_0    TI_0    RB8_0   TB8_0       9B
                9C      REN_0   SM2_0   SM1_0   SMO_0       9F
                A0                                          A3
                A4                                          A7
        IE      A8      EX0     ET0     EX1     ET1         AB
                AC      ES0     ET2     ES1     EA          AF
                B0                                          B3
                B4                                          B7
        IP      B8      PX0     PT0     PX1     PT1         BB
                BC      PS0     PT2     PS1                 BF
        SCON1   C0      RI_1    TI_1    RB8_1   TB8_1       C3
                C4      REN_1   SM2_1   SM1_1   SMO_1       C7
        T2CON   C8      CPRL2   CT2     TR2     EXEN2       CB
                CC      TCLK    RCLK    EXF2    TF2         CF
        PSW     D0      P       FL      OV      RS0         D3
                D4      RS1     F0      AC      CY          D7
        WDCON   D8      RWT     EWT     WTRF    WDIF        DB
                DC      PFI     EPFI    POR     SMOD_1      DF
                E0                                          E3
                E4                                          E7
        EIE     E8      EX2     EX3     EX4     EX5         EB
                EC      EWDI    ERTCI                       EF
                F0                                          F3
                F4                                          F7
        EIP     F8      PX2     PX3     PX4     PX5         FB
                FC      PWDI    PRTCI                       FF
        
                Alternates:
        
        SCON    98      RI      TI      RB8     TB8         9B
                9C      REN     SM2     SM1     SMO         9F
        SCON    98                                          9B
                9C                              FE          9F
        SCON0   98                                          9B
                9C                              FE_0        9F
        SCON1   C0                                          C3
                C4                              FE_1        C7
        T2CON   C8      CP_RL2  C_T2                        CB
                CC                                          CF


        AS8XCXXX ASSEMBLER                                    PAGE AT-33
        DS83C530/DS87C530 SPECIAL FUNCTION REGISTERS


        AT.10.4  Optional Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                        0x80    0x40    0x20    0x10
                        0x08    0x04    0x02    0x10
                        ----    ----    ----    ----
        DPS     0x80                                        0x10
                0x08                            SEL         0x01
        PCON    0x80    SMOD_0  SMOD0                       0x10
                0x08    GF1     GF0     STOP    IDLE        0x01
        TMOD    0x80    T1GATE  T1C_T   T1M1    T1M0        0x10
                0x08    T0GATE  T0C_T   T0M1    T0M0        0x01
        CKCON   0x80    WD1     WD0     T2M     T1M         0x10
                0x08    T0M     MD2     MD1     MD0         0x01
        EXIF    0x80    IE5     IE4     IE3     IE          0x10
                0x08    XT_RG   RGMD    RGSL    BGS         0x01
        TRIM    0x80    E4K     X12_6   TRM2    _TRM2       0x10
                0x08    TRM1    _TRM1   TRM0    _TRM0       0x01
        SBUF1   0x80    SB7     SB6     SB5     SB4         0x10
                0x08    SB3     SB2     SB1     SB0         0x01
        ROMSIZE 0x80                                        0x10
                0x08            RMS2    RMS1    RMS0        0x01
        PMR     0x80    CD1     CD0     SWB                 0x10
                0x08    XTOFF   ALEOFF  DME1    DME0        0x01
        STATUS  0x80    PIP     HIP     LIP     XTUP        0x10
                0x08    SPTA1   SPRA1   SPTA0   SPRA0       0x01
        T2MOD   0x80                                        0x10
                0x08                    T2OE    DCEN        0x01
        RTCC    0x80    SSCE    SCE     MCE     HCE         0x10
                0x08    RTCRE   RTCWE   RTCIF   RTCE        0x01
        
                Alternates:
        
        PCON    0x80    SMOD                                0x10
                0x08                                        0x01


        AS8XCXXX ASSEMBLER                                    PAGE AT-34
        DS83C530/DS87C530 SPECIAL FUNCTION REGISTERS


        AT.11  DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS 


           The DS83C550/DS87C550 Special Function Registers are selected
        using the .DS83C550 or DS87C550 assembler directives.  


        AT.11.1  SFR Map 

                        --------- 4 Bytes ----------
                        ----    ----    ----    ----
                80      PORT0   SP      DPL     DPH         83
                84      DPL1    DPH1    DPS     PCON        87
                88      TCON    TMOD    TL0     TL1         8B
                8C      TH0     TH1     CKCON               8F
                90      PORT1   RCON                        93
                94                                          97
                98      SCON0   SBUF0                       9B
                9C                              PMR         9F
                A0      PORT2   SADDR0  SADDR1              A3
                A4                                          A7
                A8      IE      CMPL0   CMPL1   CMPL2       AB
                AC      CPTL0   CPTL1   CPTL2   CPTL3       AF
                B0      PORT3           ADCON1  ADCON2      B3
                B4      ADMSB   ADLSD   WINHI   WINLO       B7
                B8      IP      SADEN0  SADEN1              BB
                BC                      T2CON   T2MOD       BF
                C0      PORT4           ROMSIZE             C3
                C4      PORT5   STATUS          TA          C7
                C8      T2IR    CMPH0   CMPH1   CMPH2       CB
                CC      CPTH0   CPTH1   CPTH2   CPTH3       CF
                D0      PSW             PW0FG   PW1FG       D3
                D4      PW2FG   PW3FG   PWMADR              D7
                D8      SCON1   SBUF1                       DB
                DC      PWM0    PWM1    PWM2    PWM3        DF
                E0      ACC     PW01CS  PW23CS  PW01CON     E3
                E4      PW23CON         RLOADL  RLOADH      E7
                E8      EIE             T2SEL   CTCON       EB
                EC      TL2     TH2     SETR    RSTR        EF
                F0      B       PORT6                       F3
                F4                                          F7
                F8      EIP                                 FB
                FC                              WDCON       FF
        
                Alternates:
        
                80      P0                                  83
                90      P1                                  93
                98      SCON    SBUF                        9B
                A0      P2                                  A3
                B0      P3                                  B3
                C0      P4                                  C3


        AS8XCXXX ASSEMBLER                                    PAGE AT-35
        DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS


                C4      P5                                  C7
                F0              PORT6                       F3


        AS8XCXXX ASSEMBLER                                    PAGE AT-36
        DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS


        AT.11.2  Bit Addressable Registers:  Generic 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
        PORT0   80      P0.7    P0.6    P0.5    P0.4        83
                84      P0.3    P0.2    P0.1    P0.0        87
        TCON    88      TCON.0  TCON.1  TCON.2  TCON.3      8B
                8C      TCON.4  TCON.5  TCON.6  TCON.7      8F
        PORT1   90      P1.0    P1.1    P1.2    P1.3        93
                94      P1.4    P1.5    P1.6    P1.7        97
        SCON0   98      SCON0.0 SCON0.1 SCON0.2 SCON0.3     9B
                9C      SCON0.4 SCON0.5 SCON0.6 SCON0.7     9F
        PORT2   A0      P2.0    P2.1    P2.2    P2.3        A3
                A4      P2.4    P2.5    P2.6    P2.7        A7
        IE      A8      IE.0    IE.1    IE.2    IE.3        AB
                AC      IE.4    IE.5    EI.6    IE.7        AF
        PORT3   B0      P3.0    P3.1    P3.2    P3.3        B3
                B4      P3.4    P3.5    P3.6    P3.7        B7
        IP      B8      IP.0    IP.1    IP.2    IP.3        BB
                BC      IP.4    IP.5    IP.6    IP.7        BF
        PORT4   C0      P4.0    P4.1    P4.2    P4.3        C3
                C4      P4.4    P4.5    P4.6    P4.7        C7
        T2IR    C8      T2IR.0  T2IR.1  T2IR.2  T2IR.3      CB
                CC      T2IR.4  T2IR.5  T2IR.6  T2IR.7      CF
        PSW     D0      PSW.0   PSW.1   PSW.2   PSW.3       D3
                D4      PSW.4   PSW.5   PSW.6   PSW.7       D7
        SCON1   D8      SCON1.0 SCON1.1 SCON1.2 SCON1.3     DB
                DC      SCON1.4 SCON1.5 SCON1.6 SCON1.7     DF
        ACC     E0      ACC.0   ACC.1   ACC.2   ACC.3       E3
                E4      ACC.4   ACC.5   ACC.6   ACC.7       E7
        EIE     E8      EIE.0   EIE.1   EIE.2   EIE.3       EB
                EC      EIE.4   EIE.5   EIE.6   EIE.7       EF
        B       F0      B.0     B.1     B.2     B.3         F3
                F4      B.4     B.5     B.6     B.7         F7
        EIP     F8      EIP.0   EIP.1   EIP.2   EIP.3       FB
                FC      EIP.4   EIP.5   EIP.6   EIP.7       FF
        
                        Alternates:
        
        PORT0   80      PORT0.7 PORT0.6 PORT0.5 PORT0.4     83
                84      PORT0.3 PORT0.2 PORT0.1 PORT0.0     87
        PORT1   90      PORT1.0 PORT1.1 PORT1.2 PORT1.3     93
                94      PORT1.4 PORT1.5 PORT1.6 PORT1.7     97
        SCON    98      SCON.0  SCON.1  SCON.2  SCON.3      9B
                9C      SCON.4  SCON.5  SCON.6  SCON.7      9F
        PORT2   A0      PORT2.0 PORT2.1 PORT2.2 PORT2.3     A3
                A4      PORT2.4 PORT2.5 PORT2.6 PORT2.7     A7
        PORT3   B0      PORT3.0 PORT3.1 PORT3.2 PORT3.3     B3
                B4      PORT3.4 PORT3.5 PORT3.6 PORT3.7     B7
        PORT4   C0      PORT4.0 PORT4.1 PORT4.2 PORT4.3     C3
                C4      PORT4.4 PORT4.5 PORT4.6 PORT4.7     C7


        AS8XCXXX ASSEMBLER                                    PAGE AT-37
        DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS


        AT.11.3  Bit Addressable Registers:  Specific 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                80                                          83
                84                                          87
        TCON    88      IT0     IE0     IT1     IE1         8B
                8C      TR0     TF0     TR1     TF1         8F
                90                                          93
                94                                          97
        SCON0   98      RI_0    TI_0    RB8_0   TB8_0       9B
                9C      REN_0   SM2_0   SM1_0   SMO_0       9F
                A0                                          A3
                A4                                          A7
        IE      A8      EX0     ET0     EX1     ET1         AB
                AC      ES0     ET2     ES1     EA          AF
                B0                                          B3
                B4                                          B7
        IP      B8      PX0     PT0     PX1     PT1         BB
                BC      PS0     PS1     PAD                 BF
        PORT4   C0      CMSR0   CMSR1   CMSR2   CMSR3       C3
                C4      CMSR4   CMSR5   CMT0    CMT1        C7
        T2IR    C8      CF0     CF1     CF2     CF3         CB
                CC      CM0F    CM1F    CM2F                CF
        PSW     D0      P       FL      OV      RS0         D3
                D4      RS1     F0      AC      CY          D7
        SCON1   D8      RI_1    TI_1    RB8_1   TB8_1       DB
                DC      REN_1   SM2_1   SM1_1   SMO_1       DF
                E0                                          E3
                E4                                          E7
        EIE     E8      EX2     EX3     EX4     EX5         EB
                EC      ECM0    ECM1    ECM2    ET2         EF
                F0                                          F3
                F4                                          F7
        EIP     F8      PX2     PX3     PX4     PX5         FB
                FC      PCM0    PCM1    PCM2    PT2         FF
        
                Alternates:
        
        SCON    98      RI      TI      RB8     TB8         9B
                9C      REN     SM2     SM1     SMO         9F
        SCON    98                                          9B
                9C                              FE          9F
        SCON0   98                                          9B
                9C                              FE_0        9F
        T2IR    C8      IE2     IE3     IE4     IE5         CB
                CC                                          CF
        SCON1   D8                                          DB
                DC                              FE_1        DF
        EIE     E8      EC0     EC1     EC2     EC3         EB
                EC                                          EF
        EIP     F8      PC0     PC1     PC2     PC3         FB


        AS8XCXXX ASSEMBLER                                    PAGE AT-38
        DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS


                FC                                          FF


        AS8XCXXX ASSEMBLER                                    PAGE AT-39
        DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS


        AT.11.4  Optional Symbols:  Control Bits 

                        ---------- 4 BITS ----------
                        ----    ----    ----    ----
                        0x80    0x40    0x20    0x10
                        0x08    0x04    0x02    0x10
                        ----    ----    ----    ----
        DPS     0x80    ID1     ID0     TSL                 0x10
                0x08                            SEL         0x01
        PCON    0x80    SMOD_0  SMOD0                       0x10
                0x08    GF1     GF0     STOP    IDLE        0x01
        TMOD    0x80    T1GATE  T1C_T   T1M1    T1M0        0x10
                0x08    T0GATE  T0C_T   T0M1    T0M0        0x01
        CKCON   0x80    WD1     WD0     T2M     T1M         0x10
                0x08    T0M     MD2     MD1     MD0         0x01
        RCON    0x80                                        0x10
                0x08    CKRDY   RGMD    RGSL    BGS         0x01
        PMR     0x80    CD1     CD0     SWB     CTM         0x10
                0x08    4X_2X   ALEOFF  DEM1    DEM0        0x01
        ADCON1  0x80   STRT_BSY EOC     CONT_SS ADEX        0x10
                0x08    WCQ     WCM     ADON    WCIO        0x01
        ADCON2  0x80    OUTCF   MUX2    MUX1    MUX0        0x10
                0x08    APS3    APS2    APS1    APS0        0x01
        T2CON   0x80    TF2     EXF2    RCLK    TCLK        0x10
                0x08    EXEN2   TR2     CT2     CPRL2       0x01
        T2MOD   0x80                                        0x10
                0x08                    T2OE    DCEN        0x01
        PORT5   0x80    ADC7    ADC6    ADC5    ADC4        0x10
                0x08    ADC3    ADC2    ADC1    ADC0        0x01
        ROMSIZE 0x80                                        0x10
                0x08            RMS2    RMS1    RMS0        0x01
        STATUS  0x80    PIP     HIP     LIP     XTUP        0x10
                0x08    SPTA1   SPRA1   SPTA0   SPRA0       0x01
        PWMADR  0x80    ADRS                                0x10
                0x08                    PWE1    PWE0        0x01
        PW01CS  0x80    PW0S2   PW0S1   PW0S0   PW0EN       0x10
                0x08    PW1S2   PW1S1   PW1S0   PW1EN       0x01
        PW23CS  0x80    PW2S2   PW2S1   PW2S0   PW2EN       0x10
                0x08    PW3S2   PW3S1   PW3S0   PW3EN       0x01
        PW01CON 0x80    PW0F    PW0DC   PW0OE   PW0T_C      0x10
                0x08    PW1F    PW1DC   PW1OE   PW1T_C      0x01
        PW23CON 0x80    PW2F    PW2DC   PW2OE   PW2T_C      0x10
                0x08    PW3F    PW3DC   PW3OE   PW3T_C      0x01
        T2SEL   0x80    TF2S    TF2BS           TF2B        0x10
                0x08                    T2P1    T2P0        0x01
        CTCON   0x80    _CT3    CT3     _CT2    CT2         0x10
                0x08    _CT1    CT1     _CT0    CT0         0x01
        SETR    0x80    TGFF1   TGFF0   CMS5    CMS4       0x10
                0x08    CMS3    CMS2    CMS1    CMS0        0x01
        RSTR    0x80    CMTE1   CMTE0   CMR5    CMR4        0x10
                0x08    CMR3    CMR2    CMR1    CMR0        0x01
        PORT6   0x80    STADC           PWMC1   PWMC0       0x10


        AS8XCXXX ASSEMBLER                                    PAGE AT-40
        DS83C550/DS87C550 SPECIAL FUNCTION REGISTERS


                0x08    PWMO3   PWMO2   PWMO1   PWMO0       0x01
        WDCON   0x80    SMOD_1  POR     EPF1    PF1         0x10
                0x08    WDIF    WTRF    EWT     RWT         0x01
        
                Alternates:
        
        PCON    0x80    SMOD                                0x10
                0x08                                        0x01
        T2CON   0x80                                        0x10
                0x08                    C_T2    _RL2        0x01














                                   APPENDIX AY

                                 ASGB ASSEMBLER





        AY.1  ACKNOWLEDGEMENT 


           Thanks  to  Roger Ivie for his contribution of the ASGB cross
        assembler.  

                Roger Ivie
                ivie at cc dot usu dot edu


        AY.2  INTRODUCTION 


           The  Gameboy uses an 8-bit processor which is closely related
        to the 8080.  It is usually described as a modified Z80, but may
        be more closely understood as an enhanced 8080;  it has the 8080
        register set and many, but not all, enhanced  Z80  instructions.
        However,  even  this is not accurate, for the Gameboy also lacks
        some basic 8080 instructions (most annoyingly  SHLD  and  LHLD).
        ASGB is based on ASZ80 and therefore uses the Z80 mnemonic set. 


        AY.3  GAMEBOY REGISTER SET AND CONDITIONS 


           The following is a complete list of register designations and
        condition mnemonics:  

                byte registers - a,b,c,d,e,h,l
                register pairs - af, bc, de, hl
                word registers - pc, sp
        
                C  - carry bit set
                NC - carry bit clear
                NZ - zero bit clear
                Z  - zero bit set


        ASGB ASSEMBLER                                         PAGE AY-2
        GAMEBOY INSTRUCTION SET


        AY.4  GAMEBOY INSTRUCTION SET 


           The following tables list all Gameboy mnemnoics recognized by
        the ASGB assembler.  The designation [] refers to a required ad-
        dressing mode argument.  The following list specifies the format
        for each addressing mode supported by ASGB:  

                #data           immediate data
                                byte or word data
        
                n               byte value
        
                rg              a byte register
                                a,b,c,d,e,h,l
        
                rp              a register pair or 16-bit register
                                bc,de,hl
        
                (hl)            implied addressing or
                                register indirect addressing
        
                (label)         direct addressing
        
                label           call/jmp/jr label


           The terms data, dir, and ext may all be expression.  The term
        dir is not allowed to be an external reference.  

           Note  that  not all addressing modes are valid with every in-
        struction.  Although official information is not, as  far  as  I
        know, publically available for the Gameboy processor, many unof-
        ficial sources are available on the internet.  


        AY.4.1  .tile Directive 


        Format:  

                        .tile  /string/         or 

                        .tile ^/string/ 



        where:  string  is  a  string of ascii characters taken from the
                        set ' ', '.', '+', '*', '0', '1', '2', and  '3'.
                        The   string   must   be  a  multiple  of  eight
                        characters long.  



        ASGB ASSEMBLER                                         PAGE AY-3
        GAMEBOY INSTRUCTION SET


                /  /     represent  the  delimiting  characters.   These
                        delimiters   may   be   any   paired    printing
                        characters,  as  long  as the characters are not
                        contained within  the  string  itself.   If  the
                        delimiting  characters  do  not match, the .tile
                        directive will give the (q) error.  

             The Gameboy displays information on the screen using a pro-
        grammable character set (referred to as  "tiles"  among  Gameboy
        developers).   The ASGB cross assembler has a processor-specific
        assembler directive  to  aid  in  the  creation  of  the  game's
        character set.  

             Each  character is created from an 8x8 grid of pixels, each
        pixel of which is composed of two bits.  The .tile directive ac-
        cepts  a single string argument which is processed to create the
        byte  values  corresponding  to  the  lines  of  pixels  in  the
        character.   The  string  argument  must  be  some multiple of 8
        characters long, and be one of these characters:  

                ' ' or '0' - for the pixel value 00
                '.' or '1' - for the pixel value 01
                '+' or '2' - for the pixel value 10
                '*' or '3' - for the pixel value 11

             The .tile directive processes each 8-character group of its
        string argument to create the two-byte  value  corresponding  to
        that  line of pixels.  The example in the popular extant litera-
        ture could be done using ASGB like this:  

           0000 7C 7C                 1         .tile " *****  "
           0002 00 C6                 2         .tile "++   ++ "
           0004 C6 00                 3         .tile "..   .. "
           0006 00 FE                 4         .tile "+++++++ "
           0008 C6 C6                 5         .tile "**   ** "
           000A 00 C6                 6         .tile "++   ++ "
           000C C6 00                 7         .tile "..   .. "
           000E 00 00                 8         .tile "        "

             Or, using the synonym character set, as:  

           0010 7C 7C                10         .tile "03333300"
           0012 00 C6                11         .tile "22000220"
           0014 C6 00                12         .tile "11000110"
           0016 00 FE                13         .tile "22222220"
           0018 C6 C6                14         .tile "33000330"
           001A 00 C6                15         .tile "22000220"
           001C C6 00                16         .tile "11000110"
           001E 00 00                17         .tile "00000000"



        ASGB ASSEMBLER                                         PAGE AY-4
        GAMEBOY INSTRUCTION SET


             Since .tile is perfectly willing to assemble multiple lines
        of a character at once (as long as it is given complete rows  of
        pixels), it could even be done as:  

                .tile " *****  ++   ++ ..   .. +++++++ "
                .tile "**   ** ++   ++ ..   ..         "


        AY.4.2  Potentially Controversial Mnemonic Selection 


             Although the Gameboy processor is based on the Z80, it does
        include some features which are not present in the Z80.  The Z80
        mnemonic  set  is  not  sufficient  to describe these additional
        operations;  mnemonics must be created for the  new  operations.
        The  mnemonics ASGB uses are not the same as those used by other
        publically-available Gameboy assemblers.  


        AY.4.2.1  Auto-Indexing Loads  - 

             The  Gameboy provides instructions to load or store the ac-
        cumulator indirectly via HL and then subsequently  increment  or
        decrement HL.  ASGB uses the mnemonic 'ldd' for the instructions
        which decrement HL and 'ldi' for the instructions  which  incre-
        ment  HL.   Because the Gameboy lacks the Z80's block moves, the
        mnemonics are not otherwise needed by ASGB.  

                ldd a,(hl)      ldd (hl),a
                ldi a,(hl)      ldi (hl),a


        AY.4.2.2  Input and Output Operations  - 

             The  Gameboy  replaces the Z80's separate address space for
        I/O with a mechanism similar to the zero page addressing of pro-
        cessors  such  as  the  6800  or 6502.  All I/O registers in the
        Gameboy reside in the address range between 0xff00  and  0xffff.
        The  Gameboy adds special instructions to load and store the ac-
        cumulator from and into this page of memory.   The  instructions
        are  analogous to the Z80's in and out instructions and ASGB re-
        tains the 'in' and 'out' mnemonics for them.  

                in a,(n)        out (n),a
                in a,(c)        out (c),a

             From  ASGB's  perspective,  the  RAM  available from 0xff80
        through 0xffff is composed of unused I/O locations  rather  than
        direct-page RAM.  




        ASGB ASSEMBLER                                         PAGE AY-5
        GAMEBOY INSTRUCTION SET


        AY.4.2.3  The 'stop' Instruction  - 

             The  publically-available  documentation  for  the  Gameboy
        lists the 'stop' instruction as the two-byte instruction 10  00,
        and the other freely-available Gameboy assemblers assemble it in
        that manner.  As far as I can tell, the only rationale for  this
        is  that  the  corresponding Z80 instruction ('djnz label') is a
        two-byte instruction.  ASGB assembles 'stop' as the one-byte in-
        struction 10.  


        AY.4.3  Inherent Instructions 


                ccf             cpl
                daa             di
                ei              nop
                halt            rla
                rlca            rra
                rrca            scf
                reti            stop
                swap


        AY.4.4  Implicit Operand Instructions 


                adc a,[]        adc []
                add a,[]        add []
                and a,[]        and []
                cp a,[]         cp []
                dec a,[]        dec []
                inc a,[]        inc []
                or a,[]         or []
                rl a,[]         rl []
                rlc a,[]        rlc []
                rr a,[]         rr []
                rrc a,[]        rrc []
                sbc a,[]        sbc []
                sla a,[]        sla []
                sra a,[]        sra []
                srl a,[]        srl []
                sub a,[]        sub []
                xor a,[]        xor []




        ASGB ASSEMBLER                                         PAGE AY-6
        GAMEBOY INSTRUCTION SET


        AY.4.5  Load Instructions 


                ld rg,[]        ld [],rg
                ld (bc),a       ld a,(bc)
                ld (de),a       ld a,(de)
                ld (label),a    ld a,(label)
                ld (label),sp   ld rp,#data
                ld sp,hl        ld hl,sp
        
                ldd a,(hl)      ldd (hl),a
                ldi a,(hl)      ldi (hl),a


        AY.4.6  Call/Return Instructions 


                call C,label    ret C
                call NC,label   ret NC
                call Z,label    ret Z
                call NZ,label   ret NZ
                call label      ret
        
                rst n


        AY.4.7  Jump Instructions 


                jp C,label      jp NC,label
                jp Z,label      jp NZ,label
        
                jp (hl)         jp label
        
                jr C,label      jr NC,label
                jr Z,label      jr NZ,label
                jr label


        AY.4.8  Bit Manipulation Instructions 


                bit n,[]
                res n,[]
                set n,[]




        ASGB ASSEMBLER                                         PAGE AY-7
        GAMEBOY INSTRUCTION SET


        AY.4.9  Input and Output Instructions 


                in a,(n)        in a,(c)
                out (n),a       out (c),a


        AY.4.10  Register Pair Instructions 


                add hl,rp       add hl,sp
                add sp,#data
        
                push rp         pop rp














                                   APPENDIX BC

                                 ASRAB ASSEMBLER




             


        BC.1  ACKNOWLEDGMENT 

        Thanks to Ulrich Raich and Razaq Ijoduola for their contribution
        of the ASRAB cross assembler.  

           Ulrich Raich and Razaq Ijoduola
           PS Division
           CERN
           CH-1211 Geneva-23
                Ulrich Raich
                Ulrich dot Raich at cern dot ch




        BC.2  PROCESSOR SPECIFIC DIRECTIVES 


             The ASRAB assembler is a port of the ASZ80 assembler.  This
        assembler can process Z80, HD64180 (Z180), and Rabbit  2000/3000
        (default)  code.   The  following  processor  specific assembler
        directives specify which processor to target when processing the
        input assembler files.  

             




        ASRAB ASSEMBLER                                        PAGE BC-2
        PROCESSOR SPECIFIC DIRECTIVES


        BC.2.1  .r2k Directive 

        Format:  

                .r2k 

        The  .r2k  directive  enables processing of the Rabbit 2000/3000
        specific mnemonics.  Mnemonics not associated  with  the  Rabbit
        2000/3000 processor will be flagged with an 'o' error.  Address-
        ing modes not supported by the Rabbit 2000/3000 will be  flagged
        with  an 'a' error.  A synonym of .r2k is .r3k.  The default as-
        sembler mode is .r2k.  

             The  .r2k  directive  also  selects  the  Rabbit  2000/3000
        specific cycles count to be output.  

             


        BC.2.2  .hd64 Directive 

        Format:  

                .hd64 

        The  .hd64  directive  enables  processing of the HD64180 (Z180)
        specific mnemonics not included  in  the  Z80  instruction  set.
        Rabbit  2000/3000  mnemonics encountered will be flagged with an
        'o' error.  Addressing modes not supported by the HD64180 (Z180)
        will be flagged with an 'a' error.  A synonym of .hd64 is .z180.

             The  .hd64 directive also selects the HD64180/Z180 specific
        cycles count to be output.  

             


        BC.2.3  .z80 Directive 

        Format:  

                .z80 

        The  .z80  directive  enables  processing  of  the  Z80 specific
        mnemonics.  HD64180 and Rabbit 2000/3000 specific mnemonics will
        be flagged with an 'o' error.  Addressing modes not supported by
        the z80 will be flagged with an 'a' error.  

             The  .z80  directive  also  selects the Z80 specific cycles
        count to be output.  



        ASRAB ASSEMBLER                                        PAGE BC-3
        PROCESSOR SPECIFIC DIRECTIVES


             


        BC.2.4  The .__.CPU.  Variable 


             The  value of the pre-defined symbol '.__.CPU.' corresponds
        to the selected processor type.  The default value  is  0  which
        corresponds  to the default processor type.  The following table
        lists the processor types and associated values  for  the  ASRAB
        assembler:  

                Processor Type            .__.CPU. Value
                --------------            --------------
                 .r2k / .r3k                     0
                .hd64 / .z180                    1
                    .z80                         2


             The  variable '.__.CPU.' is by default defined as local and
        will not be output to the created .rel file.  The assembler com-
        mand line options -g or -a will not cause the local symbol to be
        output to the created .rel file.  

             The  assembler  .globl  directive may be used to change the
        variable type to global causing its definition to be  output  to
        the  .rel file.  The inclusion of the definition of the variable
        '.__.CPU.' might be a useful means of validating that seperately
        assembled  files have been compiled for the same processor type.
        The linker will report an error for variables with multiple  non
        equal definitions.  


        ASRAB ASSEMBLER                                        PAGE BC-4
        PROCESSOR SPECIFIC DIRECTIVES


        BC.3  RABBIT 2000/3000 ADDRESSING AND INSTRUCTIONS 



        BC.3.1  Instruction Symbols 


        b       Bit select
                        (000 = bit 0, 001 = bit 1,
                         010 = bit 2, 011 = bit 3,
                         100 = bit 4, 101 = bit 5,
                         110 = bit 6, 111 = bit 7)
        cc      Condition code select
                        (00 = NZ, 01 = Z, 10 = NC, 11 = C)
        d       8-bit (signed) displacement.
                Expressed in two\'s complement.
        dd      word register select-destination
                        (00 = BC, 01 = DE, 10 = HL, 11 = SP)
        dd'     word register select-alternate
                        (00 = BC', 01 = DE', 10 = HL')
        e       8-bit (signed) displacement added to PC.
        f       condition code select
                        (000 = NZ, 001 = Z, 010 = NC, 011 = C,
                         100 = LZ/NV, 101 = LO/V, 110 = P, 111 = M)
        m       the most significant bits(MSB) of a 16-bit constant
        mn      16-bit constant
        n       8-bit constant or the least significant bits(LSB)
                of a 16-bit constant
        r, g    byte register select
                        (000 = B, 001 = C, 010 = D, 011 = E,
                         100 = H, 101 = L, 111 = A)
        ss      word register select-source
                        (00 = BC, 01 = DE, 10 = HL, 11 = SP)
        v       Restart address select
                        (010 = 0020h, 011 = 0030h, 100 = 0040h,
                         101 = 0050h, 111 = 0070h)
        x       an 8-bit constant to load into the XPC
        xx      word register select
                        (00 = BC, 01 = DE, 10 = IX, 11 = SP)
        yy      word register select
                        (00 = BC, 01 = DE, 10 = IY, 11 = SP)
        zz      word register select
                        (00 = BC, 01 = DE, 10 = HL, 11 = AF)

             


        ASRAB ASSEMBLER                                        PAGE BC-5
        RABBIT 2000/3000 ADDRESSING AND INSTRUCTIONS


                C  -    carry bit set
                M  -    sign bit set
                NC -    carry bit clear
                NZ -    zero bit clear
                P  -    sign bit clear
                PE -    parity even
                V  -    overflow bit set
                PO -    parity odd
                NV -    overflow bit clear
                Z  -    zero bit set


        The  terms  m, mn, n, and x may all be expressions.  The terms b
        and v are not allowed to be external references.  


        ASRAB ASSEMBLER                                        PAGE BC-6
        RABBIT 2000/3000 ADDRESSING AND INSTRUCTIONS


        BC.3.2  Rabbit Instructions 


             The  following list of instructions (with explicit address-
        ing modes) are available in the Rabbit 2000/3000 assembler mode.
        Those instructions denoted by an asterisk (*) are additional in-
        structions not available in the HD64180 or Z80 assembler mode.  

         ADC A,n                 DEC IX                  LD A,EIR
         ADC A,r                 DEC IY                  LD A,IIR
         ADC A,(HL)              DEC r                  *LD A,XPC
         ADC A,(IX+d)            DEC ss                  LD A,(BC)
         ADC A,(IY+d)            DEC (HL)                LD A,(DE)
         ADC HL,ss               DEC (IX+d)              LD A,(mn)
         ADD A,n                 DEC (IY+d)             *LD dd,BC
         ADD A,r                 DJNZ e                 *LD dd,DE
         ADD A,(HL)                                      LD dd,mn
         ADD A,(IX+d)            EX AF,AF                LD dd,(mn)
         ADD A,(IY+d)            EX DE,HL                LD EIR,A
         ADD HL,ss               EX DE,HL               *LD HL,IX
         ADD IX,xx               EX (SP),HL             *LD HL,IY
         ADD IY,yy               EX (SP),IX             *LD HL,(HL+d)
        *ADD SP,d                EX (SP),IY             *LD HL,(IX+d)
        *ALTD                    EXX                    *LD HL,(IY+d)
        *AND HL,DE                                       LD HL,(mn)
        *AND IX,DE               INC IX                 *LD HL,(SP+n)
        *AND IY,DE               INC IY                  LD IIR,A
         AND n                   INC r                  *LD IX,HL
         AND r                   INC ss                  LD IX,mn
         AND (HL)                INC (HL)                LD IX,(mn)
         AND (IX+d)              INC (IX+d)             *LD IX,(SP+n)
         AND (IY+d)              INC (IY+d)             *LD IY,HL
                                *IOE                     LD IY,mn
         BIT b,r                *IOI                     LD IY,(mn)
         BIT b,(HL)             *IPRES                  *LD IY,(SP+n)
         BIT b,(IX+d)           *IPSET 0                 LD r,g
         BIT b,(IY+d)           *IPSET 1                 LD r,n
        *BOOL HL                *IPSET 2                 LD r,(HL)
        *BOOL IX                *IPSET 3                 LD r,(IX+d)
        *BOOL IY                                         LD r,(IY+d)
                                 JP f,mn                 LD SP,HL
         CALL mn                 JP mn                   LD SP,IX
         CCF                     JP (HL)                 LD SP,IY
         CP n                    JP (IX)                *LD XPC,A
         CP r                    JP (IY)                 LD (BC),A
         CP (HL)                 JR cc,e                 LD (DE),A
         CP (IX+d)               JR e                    LD (HL),n
         CP (IY+d)                                       LD (HL),r
         CPL                    *LCALL x,mn


        ASRAB ASSEMBLER                                        PAGE BC-7
        RABBIT 2000/3000 ADDRESSING AND INSTRUCTIONS


        *LD (HL+d),HL           *POP IP                  SBC A,n
        *LD (IX+d),HL            POP IX                  SBC A,r
         LD (IX+d),n             POP IY                  SBC A,(HL)
         LD (IX+d),r             POP zz                  SBC HL,ss
        *LD (IY+d),HL           *PUSH IP                 SBC (IX+d)
         LD (IY+d),n             PUSH IX                 SBC (IY+d)
         LD (IY+d),r             PUSH IY                 SCF
         LD (mn),A               PUSH zz                 SET b,r
         LD (mn),HL                                      SET b,(HL)
         LD (mn),IX              RA                      SET b,(IX+d)
         LD (mn),IY              RES b,r                 SET b,(IY+d)
         LD (mn),ss              RES b,(HL)              SLA r
        *LD (SP+n),HL            RES b,(IX+d)            SLA (HL)
        *LD (SP+n),IX            RES b,(IY+d)            SLA (IX+d)
        *LD (SP+n),IY            RET                     SLA (IY+d)
         LDD                     RET f                   SRA r
         LDDR                   *RETI                    SRA (HL)
         LDI                    *RL DE                   SRA (IX+d)
         LDIR                    RL r                    SRA (IY+d)
        *LDP HL,(HL)             RL (HL)                 SRL r
        *LDP HL,(IX)             RL (IX+d)               SRL (HL)
        *LDP HL,(IY)             RL (IY+d)               SRL (IX+d)
        *LDP HL,(mn)             RLA                     SRL (IY+d)
        *LDP IX,(mn)             RLC r                   SUB n
        *LDP IY,(mn)             RLC (HL)                SUB r
        *LDP (HL),HL             RLC (IX+d)              SUB (HL)
        *LDP (IX),HL             RLC (IY+d)              SUB (IX+d)
        *LDP (IY),HL             RLCA                    SUB (IY+d)
        *LDP (mn),HL            *RR DE
        *LDP (mn),IX            *RR HL                   XOR n
        *LDP (mn),IY            *RR IX                   XOR r
         LJP x,mn               *RR IY                   XOR (HL)
         LRET                    RR r                    XOR (IX+d)
                                 RR (HL)                 XOR (IY+d)
        *MUL                     RR (IX+d)
                                 RR (IY+d)
         NEG                     RRC r
         NOP                     RRC (HL)
                                 RRC (IX+d)
        *OR HL,DE                RRC (IY+d)
        *OR IX,DE                RRCA
        *OR IY,DE                RST v
         OR n
         OR r
         OR (HL)
         OR (IX+d)
         OR (IY+d)

             




        ASRAB ASSEMBLER                                        PAGE BC-8
        Z80/HD64180 ADDRESSING AND INSTRUCTIONS


        BC.4  Z80/HD64180 ADDRESSING AND INSTRUCTIONS 

        The following list specifies the format for each Z80/HD64180 ad-
        dressing mode supported by ASZ80:  

                #data           immediate data
                                byte or word data
        
                n               byte value
        
                rg              a byte register
                                a,b,c,d,e,h,l
        
                rp              a register pair
                                bc,de,hl
        
                (hl)            implied addressing or
                                register indirect addressing
        
                (label)         direct addressing
        
                (ix+offset)     indexed addressing with
                 offset(ix)     an offset
        
                label           call/jmp/jr label

        The  terms  data,  n, label, and offset, may all be expressions.
        The terms dir and offset are not allowed to be  external  refer-
        ences.  

             The  following tables list all Z80/HD64180 mnemonics recog-
        nized by the ASRAB assembler.  The designation []  refers  to  a
        required addressing mode argument.  Note that not all addressing
        modes are valid with every instruction, refer to the Z80/HD64180
        technical data for valid modes.  

             


        ASRAB ASSEMBLER                                        PAGE BC-9
        Z80/HD64180 ADDRESSING AND INSTRUCTIONS


        BC.4.1  Inherent Instructions 

                ccf             cpd
                cpdr            cpi
                cpir            cpl
                daa             di
                ei              exx
                halt            neg
                nop             reti
                retn            rla
                rlca            rld
                rra             rrca
                rrd             scf

             


        BC.4.2  Implicit Operand Instructions 

                adc     a,[]            adc     []
                add     a,[]            add     []
                and     a,[]            and     []
                cp      a,[]            cp      []
                dec     a,[]            dec     []
                inc     a,[]            inc     []
                or      a,[]            or      []
                rl      a,[]            rl      []
                rlc     a,[]            rlc     []
                rr      a,[]            rr      []
                rrc     a,[]            rrc     []
                sbc     a,[]            sbc     []
                sla     a,[]            sla     []
                sra     a,[]            sra     []
                srl     a,[]            srl     []
                sub     a,[]            sub     []
                xor     a,[]            xor     []

             


        ASRAB ASSEMBLER                                       PAGE BC-10
        Z80/HD64180 ADDRESSING AND INSTRUCTIONS


        BC.4.3  Load Instruction 

                ld      rg,[]           ld      [],rg
                ld      (bc),a          ld      a,(bc)
                ld      (de),a          ld      a,(de)
                ld      (label),a       ld      a,(label)
                ld      (label),rp      ld      rp,(label)
                ld      i,a             ld      r,a
                ld      a,i             ld      a,r
                ld      sp,hl           ld      sp,ix
                ld      sp,iy           ld      rp,#data
                ldd                     lddr
                ldi                     ldir

             


        BC.4.4  Call/Return Instructions 

                call    C,label         ret     C
                call    M,label         ret     M
                call    NC,label        ret     NC
                call    NZ,label        ret     NZ
                call    P,label         ret     P
                call    PE,label        ret     PE
                call    PO,label        ret     PO
                call    Z,label         ret     Z
                call    label           ret

             


        BC.4.5  Jump and Jump to Subroutine Instructions 

                jp      C,label         jp      M,label
                jp      NC,label        jp      NZ,label
                jp      P,label         jp      PE,label
                jp      PO,label        jp      Z,label
                jp      (hl)            jp      (ix)
                jp      (iy)            jp      label
                djnz    label
                jr      C,label         jr      NC,label
                jr      NZ,label        jr      Z,label
                jr      label

             


        ASRAB ASSEMBLER                                       PAGE BC-11
        Z80/HD64180 ADDRESSING AND INSTRUCTIONS


        BC.4.6  Bit Manipulation Instructions 

                bit     n,[]
                res     n,[]
                set     n,[]

             


        BC.4.7  Interrupt Mode and Reset Instructions 

                im      n
                im      n
                im      n
                rst     n

             


        BC.4.8  Input and Output Instructions 

                in      a,(n)           in      rg,(c)
                ind                     indr
                ini                     inir
                out     (n),a           out     (c),rg
                outd                    otdr
                outi                    otir

             


        BC.4.9  Register Pair Instructions 

                add     hl,rp           add     ix,rp
                add     iy,rp
                adc     hl,rp           sbc     hl,rp
                ex      (sp),hl         ex      (sp),ix
                ex      (sp),iy
                ex      de,hl
                ex      af,af'
                push    rp              pop     rp

             


        ASRAB ASSEMBLER                                       PAGE BC-12
        Z80/HD64180 ADDRESSING AND INSTRUCTIONS


        BC.4.10  HD64180 Specific Instructions 

                in0     rg,(n)
                out0    (n),rg
                otdm                    otdmr
                otim                    otimr
                mlt     bc              mlt     de
                mlt     hl              mlt     sp
                slp
                tst     a
                tstio   #data














                                   APPENDIX BI

                                 ASZ80 ASSEMBLER





        BI.1  .z80 DIRECTIVE 

        Format:  

                .z80 

        The  .z80  directive enables processing of only the z80 specific
        mnemonics.  HD64180/Z180 mnemonics encountered without the .hd64
        directive will be flagged with an 'o' error.  

             The  .z80  directive  also  selects the Z80 specific cycles
        count to be output.  


        BI.2  .hd64 DIRECTIVE 

        Format:

                .hd64

        The  .hd64  directive  enables  processing  of  the HD64180/Z180
        specific mnemonics not included  in  the  Z80  instruction  set.
        HD64180/Z180  mnemonics  encountered without the .hd64 directive
        will be flagged with an 'o' error.  A synonym of .hd64 is .z180. 

             The  .hd64 directive also selects the HD64180/Z180 specific
        cycles count to be output.  




        ASZ80 ASSEMBLER                                        PAGE BI-2
        THE .__.CPU.  VARIABLE


        BI.3  THE .__.CPU.  VARIABLE 


             The  value of the pre-defined symbol '.__.CPU.' corresponds
        to the selected processor type.  The default value  is  0  which
        corresponds  to the default processor type.  The following table
        lists the processor types and associated values  for  the  ASZ80
        assembler:  

                Processor Type            .__.CPU. Value
                --------------            --------------
                    .z80                         0
                .hd64 / .z180                    1


             The  variable '.__.CPU.' is by default defined as local and
        will not be output to the created .rel file.  The assembler com-
        mand line options -g or -a will not cause the local symbol to be
        output to the created .rel file.  

             The  assembler  .globl  directive may be used to change the
        the variable type to global causing its definition to be  output
        to  the .rel file.  The inclusion of the definition of the vari-
        able '.__.CPU.' might be  a  useful  means  of  validating  that
        seperately  assembled files have been compiled for the same pro-
        cessor type.  The linker will report an error for variables with
        multiple non equal definitions.  


        BI.4  Z80 REGISTER SET AND CONDITIONS 


             The  following  is a complete list of register designations
        and condition mnemonics:  

                byte registers  -       a,b,c,d,e,h,l,i,r
                register pairs  -       af,af',bc,de,hl
                word registers  -       pc,sp,ix,iy

                C -     carry bit set
                M -     sign bit set
                NC -    carry bit clear
                NZ -    zero bit clear
                P -     sign bit clear
                PE -    parity even
                PO -    parity odd
                Z -     zero bit set




        ASZ80 ASSEMBLER                                        PAGE BI-3
        Z80 INSTRUCTION SET


        BI.5  Z80 INSTRUCTION SET 


             The following list specifies the format for each addressing
        mode supported by ASZ80:  

                #data           immediate data
                                byte or word data

                n               byte value

                rg              a byte register
                                a,b,c,d,e,h,l

                rp              a register pair
                                bc,de,hl

                (hl)            implied addressing or
                                register indirect addressing

                (label)         direct addressing

                offset(ix)      indexed addressing with
                                an offset

                label           call/jmp/jr label

        The terms data, n, label, and offset may all be expressions.  

           Note  that  not all addressing modes are valid with every in-
        struction, refer to  the  Z80/HD64180/Z180  technical  data  for
        valid modes.  

             The  following  tables  list all Z80/HD64180/Z180 mnemonics
        recognized by the ASZ80 assembler.  The designation [] refers to
        a required addressing mode argument.  


        ASZ80 ASSEMBLER                                        PAGE BI-4
        Z80 INSTRUCTION SET


        BI.5.1  Inherent Instructions 

                ccf             cpd
                cpdr            cpi
                cpir            cpl
                daa             di
                ei              exx
                halt            neg
                nop             reti
                retn            rla
                rlca            rld
                rra             rrca
                rrd             scf


        BI.5.2  Implicit Operand Instructions 

                adc     a,[]            adc     []
                add     a,[]            add     []
                and     a,[]            and     []
                cp      a,[]            cp      []
                dec     a,[]            dec     []
                inc     a,[]            inc     []
                or      a,[]            or      []
                rl      a,[]            rl      []
                rlc     a,[]            rlc     []
                rr      a,[]            rr      []
                rrc     a,[]            rrc     []
                sbc     a,[]            sbc     []
                sla     a,[]            sla     []
                sra     a,[]            sra     []
                srl     a,[]            srl     []
                sub     a,[]            sub     []
                xor     a,[]            xor     []


        ASZ80 ASSEMBLER                                        PAGE BI-5
        Z80 INSTRUCTION SET


        BI.5.3  Load Instruction 

                ld      rg,[]           ld      [],rg
                ld      (bc),a          ld      a,(bc)
                ld      (de),a          ld      a,(de)
                ld      (label),a       ld      a,(label)
                ld      (label),rp      ld      rp,(label)
                ld      i,a             ld      r,a
                ld      a,i             ld      a,r
                ld      sp,hl           ld      sp,ix
                ld      sp,iy           ld      rp,#data

                ldd                     lddr
                ldi                     ldir


        BI.5.4  Call/Return Instructions 

                call    C,label         ret     C
                call    M,label         ret     M
                call    NC,label        ret     NC
                call    NZ,label        ret     NZ
                call    P,label         ret     P
                call    PE,label        ret     PE
                call    PO,label        ret     PO
                call    Z,label         ret     Z
                call    label           ret


        BI.5.5  Jump and Jump to Subroutine Instructions 

                jp      C,label         jp      M,label
                jp      NC,label        jp      NZ,label
                jp      P,label         jp      PE,label
                jp      PO,label        jp      Z,label

                jp      (hl)            jp      (ix)
                jp      (iy)            jp      label

                djnz    label

                jr      C,label         jr      NC,label
                jr      NZ,label        jr      Z,label
                jr      label


        ASZ80 ASSEMBLER                                        PAGE BI-6
        Z80 INSTRUCTION SET


        BI.5.6  Bit Manipulation Instructions 

                bit     n,[]
                res     n,[]
                set     n,[]


        BI.5.7  Interrupt Mode and Reset Instructions 

                im      n
                im      n
                im      n
                rst     n


        BI.5.8  Input and Output Instructions 

                in      a,(n)           in      rg,(c)
                ind                     indr
                ini                     inir

                out     (n),a           out     (c),rg
                outd                    otdr
                outi                    otir


        BI.5.9  Register Pair Instructions 

                add     hl,rp           add     ix,rp
                add     iy,rp

                adc     hl,rp           sbc     hl,rp

                ex      (sp),hl         ex      (sp),ix
                ex      (sp),iy
                ex      de,hl
                ex      af,af'

                push    rp              pop     rp


        ASZ80 ASSEMBLER                                        PAGE BI-7
        Z80 INSTRUCTION SET


        BI.5.10  HD64180/Z180 Specific Instructions 

                in0     rg,(n)
                out0    (n),rg

                otdm                    otdmr
                otim                    otimr

                mlt     bc              mlt     de
                mlt     hl              mlt     sp

                slp

                tst     a
                tstio   #data