.ROMBANKMAP
BANKSTOTAL 4
BANKSIZE $70
BANKS 1
BANKSIZE $4000
BANKS 3
.ENDRO

.MEMORYMAP
SLOTSIZE $4000
DEFAULTSLOT 0
SLOT 0 $0000
SLOT 1 $4000
.ENDME

; gbs_wrap.s
.DB "GBS"			; ident
.DB 1				; version
.DB 1				; track count
.DB 1				; first track
.DW $0000			; load address
.DW INIT			; init address
.DW PLAY			; play address
.DW $FEFF			; stack pointer
.DB 0				; timer modulo
.DB 0				; timer control
.ORG $10			; title
.DB "TITLE", 0
.ORG $30			; author
.DB "AUTHOR", 0
.ORG $50			; copyright
.DB "COPYRIGHT", 0

.EMPTYFILL $c9					; ret.

.DEFINE Clock $C000

.BANK 1 SLOT 0
.ORG $0
.SECTION "Main" FORCE
LOAD:
INIT:
	ld	HL, $FF26
	ld	A, $80					; sound enable
	ldd	(HL), A
	ld	A, %11111111			; pan
	ldd	(HL), A
	ld	A, %01110111			; master volume
	ldd	(HL), A

	ld	A, $40
	ldh	($11), A				; pulse duty / length
	ldh	($16), A
	ld	A, $C4
	ldh	($12), A				; volume
	ld	A, $95
	ldh ($17), A
	
	ld	HL, Clock
	ld	(HL), 1
	inc	HL
	ld	(HL), $3F
	ret

PLAY:
	ld	HL, Clock
	ld	A, (HL)
	dec	A
	jr	z, +
	ld	(HL), A
	ret
+	ld	A, 6
	ldi	(HL), A
	ld	A, (HL)
	inc	A
	and	$3F
	ld	(HL), A

	ld	B, 0
	ld	C, A

	ld	HL, cir_pu1
	add	HL, BC
	ld	A, (HL)
	cp	$FF
	jr	z, +
	rlca
	ld	D, 0
	ld	E, A
	ld	HL, gb_periods
	add	HL, DE
	ldi	A, (HL)
	ldh	($13), A
	ldi	A, (HL)
	ld	E, $80
	or	E
	ldh	($14), A
+
	ld	HL, cir_pu2
	add	HL, BC
	ld	A, (HL)
	cp	$FF
	jr	z, +
	rlca
	ld	D, 0
	ld	E, A
	ld	HL, gb_periods
	add	HL, DE
	ldi	A, (HL)
	ldh	($18), A
	ldi	A, (HL)
	ld	E, $80
	or	E
	ldh	($19), A
+
	ret
.ENDS

cir_pu1:
.DB $30,  -1,  -1, $2E,  -1,  -1, $30,  -1
.DB $33,  -1,  -1,  -1,  -1,  -1,  -1,  -1
.DB $30,  -1, $2E,  -1, $30,  -1, $33,  -1
.DB  -1,  -1, $35,  -1, $30,  -1, $2E,  -1
.DB $30,  -1, $2E,  -1, $30,  -1, $33,  -1
.DB  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1
.DB $30,  -1, $2E,  -1, $30,  -1, $37,  -1
.DB  -1,  -1, $37,  -1, $35,  -1,  -1,  -1

cir_pu2:
.DB $27,  -1,  -1, $27,  -1,  -1, $27,  -1
.DB $30,  -1,  -1,  -1,  -1,  -1,  -1,  -1
.DB $27,  -1, $27,  -1, $27,  -1, $30,  -1
.DB  -1,  -1, $30,  -1, $2b,  -1, $2B,  -1
.DB $27,  -1, $27,  -1, $27,  -1, $30,  -1
.DB  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1
.DB $27,  -1, $27,  -1, $27,  -1, $33,  -1
.DB  -1,  -1, $33,  -1, $32,  -1,  -1,  -1

gb_periods:
.DW $0000, $0000, $0000, $0000, $0000, $0000, $0000, $0000, $0000, $0000, $0000, $0000
.DW $002C, $009D, $0107, $016B, $01C9, $0223, $0277, $02C7, $0312, $0358, $039B, $03DA
.DW $0416, $044E, $0483, $04B5, $04E5, $0511, $053B, $0563, $0589, $05AC, $05CE, $05ED
.DW $060B, $0627, $0642, $065B, $0672, $0689, $069E, $06B2, $06C4, $06D6, $06E7, $06F7
.DW $0706, $0714, $0721, $072D, $0739, $0744, $074F, $0759, $0762, $076B, $0773, $077B
.DW $0783, $078A, $0790, $0797, $079D, $07A2, $07A7, $07AC, $07B1, $07B6, $07BA, $07BE
.DW $07C1, $07C5, $07C8, $07CB, $07CE, $07D1, $07D4, $07D6, $07D9, $07DB, $07DD, $07DF
.DW $07E1, $07E2, $07E4, $07E6, $07E7, $07E9, $07EA, $07EB, $07EC, $07ED, $07EE, $07EF

; WLA DX is not actually designed with producing non-ROM files in mind