8bitlenser/lenser/atari/viewer/gr8.s
2026-07-03 19:35:35 -07:00

42 lines
1.1 KiB
ArmAsm

; lenser -- Atari GR.8 (ANTIC mode F) hi-res viewer, self-booting
; 320x192, two tones. Appended data from $4000 ...
; $4000/$5000 bitmap (1 bit per pixel, 4K split)
; $6000 two bytes, background reg then foreground reg
;
; assembled by atari/viewer/assemble.py via xa
* = $2000
boot:
.byte 0
.byte 0 ; sector count (patched)
.word $2000
.word binit
cont:
lda #$22
sta $22f ; SDMCTL
lda #<dlist
sta $230
lda #>dlist
sta $231
lda #$00
sta $26f ; GPRIOR = 0
lda $6000
sta $2c6 ; COLPF2 (background)
sta $2c8 ; COLBAK (border) = background
lda $6001
sta $2c5 ; COLPF1 (foreground luminance)
#include "awyt.i"
binit:
rts
dlist:
.byte $70,$70,$70
.byte $4f ; LMS + mode F
.word $4000
.dsb 101,$0f
.byte $4f
.word $5000
.dsb 89,$0f
.byte $41
.word dlist