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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:
; it'll fire on unused lines, but harmlessly
jmp fake
; audio sample; low nybble
ldx #0
lda (sample_ptr,x)
sta temp2
.macro fake1
jmp fake
; audio sample; low nybble
ldx #0
lda (sample_ptr,x)
sta temp2
; high nybble
lsr a
lsr a
lsr a
lsr a
; set the volume-only bit
ora #$10
pha
; high nybble
lsr a
lsr a
lsr a
lsr a
; set the volume-only bit
ora #$10
pha
; low nybble
lda temp2
and #$0f
; set the volume-only bit
ora #$10
lda #0
pha
; low nybble
lda temp2
and #$0f
; set the volume-only bit
ora #$10
lda #0
pha
.endmacro
fake:
lda #18
@ -187,24 +189,26 @@ each_scanline:
inner_scanline
; Increment sample ptr
jmp audio_cont
inc sample_ptrl
bne audio_cont
inc sample_ptrh
.macro audio_inc
; Increment sample ptr
jmp audio_cont
inc sample_ptrl
bne audio_cont
inc sample_ptrh
lda sample_ptrh
cmp #.hibyte(audio_samples_end)
bne audio_cont
lda sample_ptrh
cmp #.hibyte(audio_samples_end)
bne audio_cont
lda sample_ptrl
cmp #.lobyte(audio_samples_end)
bne audio_cont
lda sample_ptrl
cmp #.lobyte(audio_samples_end)
bne audio_cont
lda #.lobyte(audio_samples)
sta sample_ptrl
lda #.hibyte(audio_samples)
sta sample_ptrh
lda #.lobyte(audio_samples)
sta sample_ptrl
lda #.hibyte(audio_samples)
sta sample_ptrh
.endmacro
audio_cont:
@ -212,11 +216,11 @@ audio_cont:
lda VCOUNT
cmp #130 ;#130
;bne each_scanline
bne foo
bne each_scanline
;bne foo
jmp wait_start
foo:
jmp each_scanline
;foo:
;jmp each_scanline
.endproc