; ports description and include file
;for NeoGS software projects, v0.3
;
; bits degisnation:
; B_* - bit position (0,1,2,3,4,5,6,7),
; M_* - bit mask (1,2,4,8,#10,#20,#40,#80)
; C_* - constants to be used
;
; part of NeoGS project
;
; (c) 2008 NedoPC
;ZX-side ports
GSCOM=0xBB ;write-only, command for NGS
GSSTAT=0xBB ;read-only, command and data bits
; (positions given immediately below)
B_CBIT=0 ;Command position
M_CBIT=1 ; BIT and mask
B_DBIT=7 ;Data position
M_DBIT=0x80 ; BIT and mask
GSDAT=0xB3 ; read-write, data transfer register for NGS
GSCTR=0x33 ; write-only, control register for NGS:
;constants available given immediately below
C_GRST=0x80 ; reset constant to be written into GSCTR
C_GNMI=0x40 ; NMI constant to be written into GSCTR
C_GLED=0x20 ; LED toggle constant
;GS-side ports
MPAG=0x00 ; write-only, Memory PAGe port
;(big pages at 8000-FFFF or small at 8000-BFFF)
MPAGEX=0x10 ; write-only, Memory PAGe EXtended
;(only small pages at C000-FFFF)
ZXCMD=0x01 ; read-only, ZX CoMmanD port: here is the byte
;written by ZX into GSCOM
ZXDATRD=0x02 ; read-only, ZX DATa ReaD: a byte written by ZX
;into GSDAT appears here;
; upon reading this port, data bit is cleared
ZXDATWR=0x03 ; write-only, ZX DATa WRite: a byte written here
;is available for ZX in GSDAT;
; upon writing here, data bit is set
ZXSTAT=0x04 ; read-only, read ZX STATus:
;command and data bits.
;positions are defined by *_CBIT and *_DBIT above
CLRCBIT=0x05 ; read-write, upon either reading or writing
;this port, the Command BIT is CLeaRed
VOL1=0x06 ; write-only, volumes for sound channels 1-8
VOL2=0x07
VOL3=0x08
VOL4=0x09
VOL5=0x16
VOL6=0x17
VOL7=0x18
VOL8=0x19
; following two ports are useless and very odd. They have been
;made just because they were on the original GS and for that
; strange case when somebody too crazy have used them.
;Nevertheless, DO NOT USE THEM! They can disappear or even
;radically change functionality in future firmware releases.
DAMNPORT1=0x0A ; writing or reading this port sets data bit
;to the inverse of bit 0 into MPAG port
DAMNPORT2=0x0B ; the same as DAMNPORT1, but instead command
;bit involved, which is made equal to 5th bit of VOL4
LEDCTR=0x01 ; write-only, controls on-board LED.
;D0=0 - LED is on, D0=1 - LED is off
; reset state is LED on.
GSCFG0=0x0F ; read-write, GS ConFiG port 0:
;acts as memory cell, reads previously written
;value. Bits and fields follow:
B_NOROM=0 ; =0 - there is ROM everywhere except 4000-7FFF,
; =1 - the RAM is all around
M_NOROM=1
B_RAMRO=1 ; =1 - ram absolute addresses 0000-7FFF
;(zeroth big page) are write-protected
M_RAMRO=2
B_8CHANS=2 ; =1 - 8 channels mode
M_8CHANS=4
B_EXPAG=3 ; =1 - extended paging: both MPAG and MPAGEX are
;used to switch two memory windows
M_EXPAG=8
B_CKSEL0=4 ;these bits should be set according to the
;C_**MHZ constants below
M_CKSEL0=0x10
B_CKSEL1=5
M_CKSEL1=0x20
C_10MHZ=0x30
C_12MHZ=0x10
C_20MHZ=0x20
C_24MHZ=0x00
B_PAN4CH=6 ; =1 - 4 channels, panning
;(every channel is on left and right with two volumes)
M_PAN4CH=0x40
B_SETNCLR=7
M_SETNCLR=0x80
SCTRL=0x11 ;Serial ConTRoL: read-write,
;read: current state of below bits,
;write - see GS_info
B_SDNCS=0
M_SDNCS=1
B_MCNCS=1
M_MCNCS=2
B_MPXRS=2
M_MPXRS=4
B_MCSPD0=3
M_MCSPD0=8
B_MDHLF=4
M_MDHLF=0x10
B_MCSPD1=5
M_MCSPD1=0x20
SSTAT=0x12 ;Serial STATus:
;read-only, reads state of below bits
B_MDDRQ=0
M_MDDRQ=1
B_SDDET=1
M_SDDET=2
B_SDWP=2
M_SDWP=4
B_MCRDY=3
M_MCRDY=8
SD_SEND=0x13 ;SD card SEND, write-only,
;when written, byte transfer starts with written byte
SD_READ=0x13 ;SD card READ, read-only,
;reads byte received in previous byte transfer
SD_RSTR=0x14 ;SD card Read and STaRt, read-only, reads
;previously received byte and starts new byte transfer with #FF
MD_SEND=0x14 ;Mp3 Data SEND, write-only,
;sends byte to the mp3 data interface
MC_SEND=0x15 ;Mp3 Control SEND, write-only,
;sends byte to the mp3 control interface
MC_READ=0x15 ;Mp3 Control READ, read-only,
;reads byte that was received during previous sending of byte
DMA_MOD=0x1B
DMA_HAD=0x1C
DMA_MAD=0x1D
DMA_LAD=0x1E
DMA_CST=0x1F
;Послать код команды в регистр команд
MACRO SC cmd
LD A,cmd
OUT (GSCOM),A
ENDM
;Ожидание сброса Command bit
MACRO WC
;LOCAL
;WCLP
IN A,(GSCOM)
RRCA
JR C,$-3;WCLP
;ENDL
ENDM
;Послать данные в регистр данных
MACRO SD data
LD A,data
OUT (GSDAT),A
ENDM
;Ожидание сброса Data bit
;по сути,ожидание,пока GS не примет посланные ему данные
MACRO WD
;LOCAL
;WDLP
IN A,(GSCOM)
RLCA
JR C,$-3;WDLP
;ENDL
ENDM
;Принять данные из регистра данных
MACRO GD
IN A,(GSDAT)
ENDM
;Ожидание установки Data bit
;по сути,ожидание очередных данных от GS
MACRO WN
;LOCAL
;WNLP
IN A,(GSCOM)
RLCA
JR NC,$-3;WNLP
;ENDL
ENDM