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urk, maybe no cycles free ;)

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Brooke Vibber 2022-11-30 03:39:23 -08:00
parent 7dfa1dfb26
commit 019422e6e5
1 changed files with 43 additions and 39 deletions
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dither4.s
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@ -131,28 +131,30 @@ wait_loop:
each_scanline: each_scanline:
; it'll fire on unused lines, but harmlessly ; it'll fire on unused lines, but harmlessly
jmp fake .macro fake1
; audio sample; low nybble jmp fake
ldx #0 ; audio sample; low nybble
lda (sample_ptr,x) ldx #0
sta temp2 lda (sample_ptr,x)
sta temp2
; high nybble ; high nybble
lsr a lsr a
lsr a lsr a
lsr a lsr a
lsr a lsr a
; set the volume-only bit ; set the volume-only bit
ora #$10 ora #$10
pha pha
; low nybble ; low nybble
lda temp2 lda temp2
and #$0f and #$0f
; set the volume-only bit ; set the volume-only bit
ora #$10 ora #$10
lda #0 lda #0
pha pha
.endmacro
fake: fake:
lda #18 lda #18
@ -187,24 +189,26 @@ each_scanline:
inner_scanline inner_scanline
; Increment sample ptr .macro audio_inc
jmp audio_cont ; Increment sample ptr
inc sample_ptrl jmp audio_cont
bne audio_cont inc sample_ptrl
inc sample_ptrh bne audio_cont
inc sample_ptrh
lda sample_ptrh lda sample_ptrh
cmp #.hibyte(audio_samples_end) cmp #.hibyte(audio_samples_end)
bne audio_cont bne audio_cont
lda sample_ptrl lda sample_ptrl
cmp #.lobyte(audio_samples_end) cmp #.lobyte(audio_samples_end)
bne audio_cont bne audio_cont
lda #.lobyte(audio_samples) lda #.lobyte(audio_samples)
sta sample_ptrl sta sample_ptrl
lda #.hibyte(audio_samples) lda #.hibyte(audio_samples)
sta sample_ptrh sta sample_ptrh
.endmacro
audio_cont: audio_cont:
@ -212,11 +216,11 @@ audio_cont:
lda VCOUNT lda VCOUNT
cmp #130 ;#130 cmp #130 ;#130
;bne each_scanline bne each_scanline
bne foo ;bne foo
jmp wait_start jmp wait_start
foo: ;foo:
jmp each_scanline ;jmp each_scanline
.endproc .endproc