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Andy McFadden 2019-10-12 17:18:04 -07:00
parent d8604294bb
commit 547ecd2173
1 changed files with 31 additions and 9 deletions
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40
SourceGen/RuntimeData/Atari/2600.sym65
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@ -3,10 +3,27 @@
;
; Adapted from various online references. Comments are most directly from
; http://www.classic-games.com/atari2600/specs.html
;
; Some info from memory mirror maps by Chris Wilkson.
*SYNOPSIS Atari 2600 (VCS) registers and constants
; 128 bytes of RIOT RAM is primarily $80-ff and $180-1ff
; mirror: $xy80
; x={even}
; y={0,1,4,5,8,9,C,D}
; 4K ROM is primarily $f000-ffff
; mirror: $x000
; x = {odd}
;
; For 8K ROM, second bank is primarily $d000-dfff
; TIA write registers
; mirror: $xyz0
; x = {even}
; y = {anything}
; z = {0, 4}
VSYNC @ $00 ;W 0000 00x0 Vertical Sync Set-Clear
VBLANK @ $01 ;W xx00 00x0 Vertical Blank Set-Clear
WSYNC @ $02 ;W ---- ---- Wait for Horizontal Blank
@ -52,6 +69,7 @@ RESMP1 @ $29 ;W 0000 00x0 Reset Missle 1 to Player 1
HMOVE @ $2a ;W ---- ---- Apply Horizontal Motion
HMCLR @ $2b ;W ---- ---- Clear Horizontal Move Registers
CXCLR @ $2c ;W ---- ---- Clear Collision Latches
; $2d-3f undefined, but $3e/3f may be used for bank switching
; TIA read registers. The actual values are $0-d, but only 4 bits of the
; address are used on the hardware. I'm using $3x because that's what
@ -72,13 +90,17 @@ INPT4 @ $3c ;R x000 0000 Read Input (Trigger) 0
INPT5 @ $3d ;R x000 0000 Read Input (Trigger) 1
; PIA/RIOT (6532) registers
SWCHA @ $280 ;Port A data register (joysticks...)
SWACNT @ $281 ;Port A data direction register (DDR)
SWCHB @ $282 ;Port B data (console switches)
SWBCNT @ $283 ;Port B DDR
INTIM @ $284 ;Timer output
; mirror: $xyz0
; x = {even}
; y = {2,3,6,7,a,b,e,f}
; z = {8,a,c,e}
SWCHA @ $280 ;RW Port A data register (joysticks...)
SWACNT @ $281 ;RW Port A data direction register (DDR)
SWCHB @ $282 ;RW Port B data (console switches)
SWBCNT @ $283 ;RW Port B DDR
INTIM @ $284 ;R Timer output
TIM1T @ $294 ;set 1 clock interval
TIM8T @ $295 ;set 8 clock interval
TIM64T @ $296 ;set 64 clock interval
T1024T @ $297 ;set 1024 clock interval
TIM1T @ $294 ;W set 1 clock interval
TIM8T @ $295 ;W set 8 clock interval
TIM64T @ $296 ;W set 64 clock interval
T1024T @ $297 ;W set 1024 clock interval