mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-11-16 23:20:43 +00:00
118 lines
2.5 KiB
ArmAsm
118 lines
2.5 KiB
ArmAsm
;========================================================================
|
|
; EVERYTHING IS CYCLE COUNTED
|
|
;========================================================================
|
|
|
|
;=====================================
|
|
; Set Pattern
|
|
;=====================================
|
|
|
|
|
|
; set pattern: 11 + 12 + 22 + 22 + 22 + 19 + 18 = 126
|
|
|
|
; set_pattern_end: 11 + 16 + ...
|
|
|
|
pt3_set_pattern:
|
|
|
|
; Lookup current pattern in pattern table
|
|
current_pattern_smc:
|
|
ldy #$d1 ; 2
|
|
lda PT3_LOC+PT3_PATTERN_TABLE,Y ; 4+
|
|
|
|
; if value is $FF we are at the end of the song
|
|
cmp #$ff ; 2
|
|
bne not_done_delay_16 ; 3
|
|
;===========
|
|
; 11
|
|
|
|
|
|
is_done:
|
|
; -1
|
|
; for cycle counted version let's set DONE_SONG
|
|
; but also set to loop forever
|
|
|
|
; done with song, set it to non-zero
|
|
sta DONE_SONG ; 3
|
|
|
|
ldy PT3_LOC+PT3_LOOP ; 3
|
|
sty current_pattern_smc+1 ; 4
|
|
lda PT3_LOC+PT3_PATTERN_TABLE,Y ; 4+
|
|
jmp not_done ; 3
|
|
;============
|
|
; 16
|
|
|
|
not_done_delay_16:
|
|
inc CYCLE_WASTE ; 5
|
|
inc CYCLE_WASTE ; 5
|
|
nop
|
|
nop
|
|
nop
|
|
|
|
|
|
not_done:
|
|
|
|
; set up the three pattern address pointers
|
|
|
|
asl ; mul pattern offset by two, as word sized ; 2
|
|
tay ; 2
|
|
|
|
; point PATTERN_H/PATTERN_L to the pattern address table
|
|
|
|
clc ; 2
|
|
lda PT3_LOC+PT3_PATTERN_LOC_L ; 4
|
|
sta PATTERN_L ; 3
|
|
lda PT3_LOC+PT3_PATTERN_LOC_H ; 4
|
|
adc #>PT3_LOC ; assume page boundary ; 2
|
|
sta PATTERN_H ; 3
|
|
;===========
|
|
; 22
|
|
|
|
; First 16-bits points to the Channel A address
|
|
lda (PATTERN_L),Y ; 5+
|
|
sta note_a+NOTE_ADDR_L ; 3
|
|
iny ; 2
|
|
lda (PATTERN_L),Y ; 5+
|
|
adc #>PT3_LOC ; assume page boundary ; 2
|
|
sta note_a+NOTE_ADDR_H ; 3
|
|
iny ; 2
|
|
;===========
|
|
; 22
|
|
|
|
; Next 16-bits points to the Channel B address
|
|
lda (PATTERN_L),Y ; 5+
|
|
sta note_b+NOTE_ADDR_L ; 3
|
|
iny ; 2
|
|
lda (PATTERN_L),Y ; 5+
|
|
adc #>PT3_LOC ; assume page boundary ; 2
|
|
sta note_b+NOTE_ADDR_H ; 3
|
|
iny ; 2
|
|
;===========
|
|
; 22
|
|
|
|
; Next 16-bits points to the Channel C address
|
|
lda (PATTERN_L),Y ; 5+
|
|
sta note_c+NOTE_ADDR_L ; 3
|
|
iny ; 2
|
|
lda (PATTERN_L),Y ; 5+
|
|
adc #>PT3_LOC ; assume page boundary ; 2
|
|
sta note_c+NOTE_ADDR_H ; 2
|
|
;===========
|
|
; 19
|
|
|
|
; clear out the noise channel
|
|
lda #0 ; 2
|
|
sta pt3_noise_period_smc+1 ; 4
|
|
|
|
; Set all three channels as active
|
|
lda #3 ; 2
|
|
sta pt3_pattern_done_smc+1 ; 4
|
|
|
|
rts ; 6
|
|
;============
|
|
; 18
|
|
|
|
|
|
|
|
|
|
|
|
|