dos33fsprogs/demos/l/d4/tracker_init.s

tracker_init:

	; setup initial ay-3-8910 values (this depends on song)

init_registers_to_zero:
	ldx	#$13			; zero $70--$83
	lda	#0
;	sta	SONG_OFFSET		; also init song stuff
;	sta	SONG_COUNTDOWN
init_loop:
	sta	AY_REGS,X
	dex
	bpl	init_loop

	lda	#$38
	sta	AY_REGS+7			; $07 mixer (ABC on)
	lda	#$0E
	sta	AY_REGS+8                       ; $08 volume A
	lda	#$0C
	sta	AY_REGS+9                       ; $09 volume B
	sta	AY_REGS+10                      ; $0A volume C
tiny_tracker: more work 2022-01-11 07:59:52 +00:00			`tracker_init:`

			`; setup initial ay-3-8910 values (this depends on song)`

			`init_registers_to_zero:`
tiny_tracker: optimize some more 2022-01-15 20:58:47 +00:00			`ldx #$13 ; zero $70--$83`
tiny_tracker: more work 2022-01-11 07:59:52 +00:00			`lda #0`
tiny_tracker: optimize some more 2022-01-15 20:58:47 +00:00			`; sta SONG_OFFSET ; also init song stuff`
			`; sta SONG_COUNTDOWN`
tiny_tracker: more work 2022-01-11 07:59:52 +00:00			`init_loop:`
			`sta AY_REGS,X`
			`dex`
			`bpl init_loop`

			`lda #$38`
			`sta AY_REGS+7 ; $07 mixer (ABC on)`
tiny_tracker: optimize some more 2022-01-15 20:58:47 +00:00			`lda #$0E`
			`sta AY_REGS+8 ; $08 volume A`
			`lda #$0C`
			`sta AY_REGS+9 ; $09 volume B`
			`sta AY_REGS+10 ; $0A volume C`