snes apu code

#define _A_SONG0	$6000
#define _A_SONG1	$7000

#define _A_SAMPLE0	$8000
#define _A_SAMPLE1	$9000
#define _A_SAMPLE2	$A000
#define _A_SAMPLE3	$B000
#define _A_SAMPLE4	$C000
#define _A_SAMPLE5	$D000
#define _A_SAMPLE6	$E000
#define _A_SAMPLE7	$F000

#define _A_PITCH_TABLE	$0300

.org $0000
.dw 1024
.dw 1085
.dw 1149
.dw 1218
.dw 1290
.dw 1367
.dw 1448
.dw 1534
.dw 1625
.dw 1722
.dw 1825
.dw 1933
.dw 2048
.dw 2170
.dw 2299
.dw 2435
.dw 2580
.dw 2734
.dw 2896
.dw 3069
.dw 3251
.dw 3444
.dw 3649
.dw 3866
.dw 4096
.dw 4340
.dw 4598
.dw 4871
.dw 5160
.dw 5467
.dw 5793
.dw 6137
.dw 6507
.dw 6889
.dw 7298
.dw 7732
.dw 8192
.dw 8679
.dw 9195
.dw 9742
.dw 10321
.dw 10935
.dw 11585
.dw 12274
.dw 13003
.dw 13777
.dw 14596
.dw 15464
.dw 16383

main:
	mov y, #$00
    mov CONTROL, y
    mov a, #$0C
    movw DSPADDR, ya
    mov a, #$1C
    movw DSPADDR, ya
    mov a, #$2C
    movw DSPADDR, ya
    mov a, #$3C
    movw DSPADDR, ya
    mov a, #$3C
    movw DSPADDR, ya
    mov a, #$2D
    movw DSPADDR, ya
    mov a, #$3D
    movw DSPADDR, ya
    mov a, #$4D
    movw DSPADDR, ya
    mov a, #$6C
    mov y, #$20
    movw DSPADDR, ya
    mov a, #$5D
    mov y, #$02
    movw DSPADDR, ya
    mov a, #$00
    mov y, #$03
    movw $00, ya
main_loop:
	mov a, CPUIO0
    or a, CPUIO1
    beq main_loop
    mov a, CPUIO1
    bne push_song
    mov a, CPUIO0
    bra handle_command
    bra main_loop
push_song:
	mov a, $80
    call !push_song0_channel
	mov a, $90
    call !push_song0_channel
	mov a, $A0
    call !push_song0_channel
	mov a, $B0
    call !push_song0_channel
	mov a, $C0
    call !push_song1_channel
	mov a, $D0
    call !push_song1_channel
	mov a, $E0
    call !push_song1_channel
	mov a, $F0
    call !push_song1_channel
    jmp !main_loop
handle_command:
	mov a, CPUIO0
    and a, #$E0
    cmp a, #$20
    beq handle_load_sample_command
    cmp a, #$40
    beq handle_load_song_command
    cmp a, #$60
    beq handle_play_song_command
    mov a, CPUIO0
    cmp a, #$01
    beq kill_command
    jmp !main_loop
kill_command
	stop
handle_load_sample_command:
	mov a, CPUIO0
    and a, #$07
    call !load_sample
    jmp !main_loop
handle_load_song_command:
	mov a, CPUIO0
    and #$01
    call !load_song
    jmp !main_loop
handle_play_song_command:
	mov a, CPUIO0
    and a, #$02
    beq handle_play_song_command0
	mov a
    jmp !main_loop