68k ASM defines
Here are preliminary ASM defines for memory locations and constants. For detailed descriptions, see Memory mapped registers.
This can be made into a file and included in your ASM source code to use register names instead of their (meaningless) addresses in RAM.
SCB1 equ $0000 ;VRAM, Sprite tilemaps
FIXMAP equ $7000 ;VRAM, Fix map
SCB2 equ $8000 ;VRAM, Sprite shrink
SCB3 equ $8200 ;VRAM, Sprite Y positions and sizes
SCB4 equ $8400 ;VRAM, Sprite X positions
BLACK equ $8000
MIDBLUE equ $1007
BLUE equ $100F
MIDGREEN equ $2070
GREEN equ $20F0
MIDCYAN equ $3077
CYAN equ $30FF
MIDRED equ $4700
RED equ $4F00
MIDMAGENTA equ $5707
MAGENTA equ $5F0F
ORANGE equ $6F70
MIDYELLOW equ $6770
YELLOW equ $6FF0
MIDGREY equ $7777
WHITE equ $7FFF
RAMSTART equ $100000 ;User RAM start
PALETTES equ $400000 ;Palette RAM start
REG_P1CNT equ $300000 ;Joystick port 1
REG_DIPSW equ $300001 ;Dipswitches/Watchdog
REG_SOUND equ $320000 ;In/Out Z80
REG_STATUS_A equ $320001
REG_P2CNT equ $340000 ;Joystick port 2
REG_STATUS_B equ $380000
REG_POUTPUT equ $380001 ;Joypad port outputs
REG_SLOT equ $380021 ;Slot selection
REG_DISPENABL equ $3A0001 ;Video output ON
REG_DISPDSABL equ $3A0011 ;Video output OFF
REG_SWPROM equ $3A0013 ;Use ROM vector table
REG_CRDUNLOCK1 equ $3A0005 ;Allow /WE to pass through to memory card when low
REG_CRDLOCK1 equ $3A0015 ;Don't allow /WE to pass through to memory card
REG_CRDLOCK2 equ $3A0007 ;Don't allow /WE to pass through to memory card
REG_CRDUNLOCK2 equ $3A0017 ;Allow /WE to pass through to memory card when high
REG_BRDFIX equ $3A000B ;Use board fix tileset
REG_CRTFIX equ $3A001B ;Use ROM fix tileset
REG_SRAMLOCK equ $3A000D ;Write-protect SRAM
REG_SRAMUNLOCK equ $3A001D ;Write-unprotect SRAM
REG_PALBANK1 equ $3A000F ;Use palette bank 1
REG_PALBANK0 equ $3A001F ;Use palette bank 0 (default)
VRAM_ADDR equ $3C0000
VRAM_RW equ $3C0002
VRAM_MOD equ $3C0004
REG_HBLANKCNT equ $3C0006
REG_HBLANKPOS equ $3C0008
REG_IRQACK equ $3C000C
; BIOS calls
BIOSF_BOOTSCR equ $C00438 ;Show boot screen (and other things)
BIOSF_VBL equ $C0044A ;Multiple purposes
BIOSF_GETTIME equ $C0045C ;Set calendar addresses (10FDD2+), MVS only
BIOSF_CRDACCESS equ $C00468 ;Access memory card with specified function (check CRDF)
BIOSF_CRDREPORT equ $C0046E ;In case an error occurred ("CARD FULL" etc.), prompt user for action
BIOSF_HOWTOPLAY equ $C00474 ;Show how-to-play presentation, MVS only
BIOSF_CLEARFIX equ $C004C2 ;Clear fix layer
BIOSF_CLEARSPR equ $C004C8 ;Clear sprites
BIOSF_UPLOAD equ $C00546 ;Upload data to DRAM
BIOSF_CDDACMD equ $C0056A ;Issue CDDA command
;DMA related:
REG_DMACPYSRC equ $FF0064 ;longword: Copy source address ?
REG_DMAFILDEST equ $FF0064 ;longword: Fill destination address ?
REG_DMACPYDEST equ $FF0068 ;longword: Copy destination address ?
REG_DMAFILVAL equ $FF006C ;word: Fill value (word) ?
REG_DMASIZE equ $FF0070 ;longword?: Size (in 16 bit words)
REG_DMASTART equ $FF0060 ;byte: Start transfer ($40 ?)
REG_UPMAPSPR equ $FF0121 ;bytes (0 or 1)
REG_UPMAPPCM equ $FF0123
REG_UPMAPZ80 equ $FF0127
REG_UPMAPFIX equ $FF0129
REG_UPUNMAPSPR equ $FF0141
REG_UPUNMAPPCM equ $FF0143
REG_UPUNMAPZ80 equ $FF0147
REG_UPUNMAPFIX equ $FF0149
REG_CDDALEFTL equ $FF0188 ;CD audio levels
REG_CDDARIGHTL equ $FF018A
BIOS_SYSSTAT equ $10FD80 ;Word: ?
; Set by BIOSF_VBL
BIOS_P1CURRENT equ $10FD95 ;joystick 1 state
BIOS_P1PREVIOUS equ $10FD96 ;previous joystick 1 state
BIOS_P1CHANGE equ $10FD97 ;joystick 1 state change
BIOS_P1REPEAT equ $10FD98 ;joystick 1 repeat
BIOS_P2CURRENT equ $10FD9B ;joystick 2 state
BIOS_P2PREVIOUS equ $10FD9C ;previous joystick 2 state
BIOS_P2CHANGE equ $10FD9D ;joystick 2 state change
BIOS_P2REPEAT equ $10FD9E ;joystick 2 repeat
BIOS_STATCURNT equ $10FDAC ;joystick 1/2 start/select
BIOS_STATCHANGE equ $10FDAD ;previous joystick 1/2 start/select
; Memory card related:
BIOS_CRDF equ $10FDC4 ;byte: function to perform when calling BIOSF_CRDACCESS, see below table
BIOS_CRDRESULT equ $10FDC6 ;byte: 00 on success, else 80+ and encodes the error, see below table
BIOS_CRDPTR equ $10FDC8 ;longword: pointer to read from/write to
BIOS_CRDSIZE equ $10FDCC ;word: how much data to read/write from/to card
BIOS_CRDNGH equ $10FDCE ;word: usually game NGH. Unique identifier for the game that 'owns' the save file
BIOS_CRDFILE equ $10FDD0 ;word: each NGH has up to 16 save 'files' associated with
; Calendar, only set by MVS (all data stored in BCD)
BIOS_YEAR equ $10FDD2 ;last 2 digits of year
BIOS_MONTH equ $10FDD3
BIOS_DAY equ $10FDD4
BIOS_WEEKDAY equ $10FDD5 ;Sunday = 00, Monday = 01 ... Saturday = 06
BIOS_HOUR equ $10FDD6 ;24 hour time
BIOS_MINUTE equ $10FDD7
BIOS_SECOND equ $10FDD8
; Upload to DRAM
BIOS_UPSRC equ $10FEF8 ;longword: source address
BIOS_UPDEST equ $10FEF4 ;longword: destination address (!)
BIOS_UPSIZE equ $10FEFC ;longword: size
BIOS_UPZONE equ $10FEDA ;byte: zone (0=PRG, 1=FIX, 2=SPR, 3=Z80, 4=PCM, 5=PAT)
BIOS_UPBANK equ $10FEDB ;byte: bank