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                                   APPENDIX K

                                AS8051 ASSEMBLER





        K.1  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)


        K.2  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.  


        K.2.1  Inherent Instructions 

                nop


        K.2.6  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


        K.2.8  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


        K.2.8  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


        K.2.3  Call and Return Instructions 

                acall   label           lcall   label
                ret                     reti

        K.2.4  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