CgbSound is decompiled.

5 files changed, 359 insertions, 607 deletions

diff --git a/Makefile b/Makefile
index 32cc9df73..4b13d59db 100644
--- a/Makefile
+++ b/Makefile
@@ -131,6 +131,7 @@ $(C_BUILDDIR)/agb_flash_1m.o: CFLAGS := -O -mthumb-interwork
 $(C_BUILDDIR)/agb_flash_mx.o: CFLAGS := -O -mthumb-interwork
 
 $(C_BUILDDIR)/m4a_2.o: CC1 := tools/agbcc/bin/old_agbcc
+$(C_BUILDDIR)/m4a_3.o: CC1 := tools/agbcc/bin/old_agbcc
 $(C_BUILDDIR)/m4a_4.o: CC1 := tools/agbcc/bin/old_agbcc
 
 $(C_BUILDDIR)/record_mixing.o: CFLAGS += -ffreestanding
diff --git a/asm/m4a_3.s b/asm/m4a_3.s
deleted file mode 100644
index a842ae925..000000000
--- a/asm/m4a_3.s
+++ /dev/null
@@ -1,574 +0,0 @@
-	.include "asm/macros.inc"
-	.include "constants/gba_constants.inc"
-	.include "constants/m4a_constants.inc"
-
-	.syntax unified
-
-	.text
-
-	thumb_func_start CgbSound
-CgbSound: @ 81DEA70
-	push {r4-r7,lr}
-	mov r7, r10
-	mov r6, r9
-	mov r5, r8
-	push {r5-r7}
-	sub sp, 0x1C
-	ldr r0, =SOUND_INFO_PTR
-	ldr r0, [r0]
-	str r0, [sp, 0x4]
-	ldrb r0, [r0, 0xA]
-	cmp r0, 0
-	beq _081DEA94
-	subs r0, 0x1
-	ldr r1, [sp, 0x4]
-	strb r0, [r1, 0xA]
-	b _081DEA9A
-	.pool
-_081DEA94:
-	movs r0, 0xE
-	ldr r2, [sp, 0x4]
-	strb r0, [r2, 0xA]
-_081DEA9A:
-	movs r6, 0x1
-	ldr r0, [sp, 0x4]
-	ldr r4, [r0, 0x1C]
-_081DEAA0:
-	ldrb r1, [r4]
-	movs r0, 0xC7
-	ands r0, r1
-	adds r2, r6, 0x1
-	mov r10, r2
-	movs r2, 0x40
-	adds r2, r4
-	mov r9, r2
-	cmp r0, 0
-	bne _081DEAB6
-	b _081DEEA0
-_081DEAB6:
-	cmp r6, 0x2
-	beq _081DEAE8
-	cmp r6, 0x2
-	bgt _081DEAC4
-	cmp r6, 0x1
-	beq _081DEACA
-	b _081DEB20
-_081DEAC4:
-	cmp r6, 0x3
-	beq _081DEB00
-	b _081DEB20
-_081DEACA:
-	ldr r0, =REG_NR10
-	str r0, [sp, 0x8]
-	ldr r7, =REG_NR11
-	ldr r2, =REG_NR12
-	str r2, [sp, 0xC]
-	adds r0, 0x4
-	str r0, [sp, 0x10]
-	adds r2, 0x2
-	b _081DEB30
-	.pool
-_081DEAE8:
-	ldr r0, =REG_NR10 + 1
-	str r0, [sp, 0x8]
-	ldr r7, =REG_NR21
-	ldr r2, =REG_NR22
-	b _081DEB28
-	.pool
-_081DEB00:
-	ldr r0, =REG_NR30
-	str r0, [sp, 0x8]
-	ldr r7, =REG_NR31
-	ldr r2, =REG_NR32
-	str r2, [sp, 0xC]
-	adds r0, 0x4
-	str r0, [sp, 0x10]
-	adds r2, 0x2
-	b _081DEB30
-	.pool
-_081DEB20:
-	ldr r0, =REG_NR30 + 1
-	str r0, [sp, 0x8]
-	ldr r7, =REG_NR41
-	ldr r2, =REG_NR42
-_081DEB28:
-	str r2, [sp, 0xC]
-	adds r0, 0xB
-	str r0, [sp, 0x10]
-	adds r2, 0x4
-_081DEB30:
-	str r2, [sp, 0x14]
-	ldr r0, [sp, 0x4]
-	ldrb r0, [r0, 0xA]
-	str r0, [sp]
-	ldr r2, [sp, 0xC]
-	ldrb r0, [r2]
-	mov r8, r0
-	adds r2, r1, 0
-	movs r0, 0x80
-	ands r0, r2
-	cmp r0, 0
-	beq _081DEC26
-	movs r3, 0x40
-	adds r0, r3, 0
-	ands r0, r2
-	lsls r0, 24
-	lsrs r5, r0, 24
-	adds r0, r6, 0x1
-	mov r10, r0
-	movs r1, 0x40
-	adds r1, r4
-	mov r9, r1
-	cmp r5, 0
-	bne _081DEC4A
-	movs r0, 0x3
-	strb r0, [r4]
-	strb r0, [r4, 0x1D]
-	adds r0, r4, 0
-	str r3, [sp, 0x18]
-	bl CgbModVol
-	ldr r3, [sp, 0x18]
-	cmp r6, 0x2
-	beq _081DEB98
-	cmp r6, 0x2
-	bgt _081DEB8C
-	cmp r6, 0x1
-	beq _081DEB92
-	b _081DEBEC
-	.pool
-_081DEB8C:
-	cmp r6, 0x3
-	beq _081DEBA4
-	b _081DEBEC
-_081DEB92:
-	ldrb r0, [r4, 0x1F]
-	ldr r2, [sp, 0x8]
-	strb r0, [r2]
-_081DEB98:
-	ldr r0, [r4, 0x24]
-	lsls r0, 6
-	ldrb r1, [r4, 0x1E]
-	adds r0, r1, r0
-	strb r0, [r7]
-	b _081DEBF8
-_081DEBA4:
-	ldr r1, [r4, 0x24]
-	ldr r0, [r4, 0x28]
-	cmp r1, r0
-	beq _081DEBCC
-	ldr r2, [sp, 0x8]
-	strb r3, [r2]
-	ldr r1, =REG_WAVE_RAM
-	ldr r2, [r4, 0x24]
-	ldr r0, [r2]
-	str r0, [r1]
-	adds r1, 0x4
-	ldr r0, [r2, 0x4]
-	str r0, [r1]
-	adds r1, 0x4
-	ldr r0, [r2, 0x8]
-	str r0, [r1]
-	adds r1, 0x4
-	ldr r0, [r2, 0xC]
-	str r0, [r1]
-	str r2, [r4, 0x28]
-_081DEBCC:
-	ldr r0, [sp, 0x8]
-	strb r5, [r0]
-	ldrb r0, [r4, 0x1E]
-	strb r0, [r7]
-	ldrb r0, [r4, 0x1E]
-	cmp r0, 0
-	beq _081DEBE4
-	movs r0, 0xC0
-	b _081DEC06
-	.pool
-_081DEBE4:
-	movs r1, 0x80
-	negs r1, r1
-	strb r1, [r4, 0x1A]
-	b _081DEC08
-_081DEBEC:
-	ldrb r0, [r4, 0x1E]
-	strb r0, [r7]
-	ldr r0, [r4, 0x24]
-	lsls r0, 3
-	ldr r2, [sp, 0x10]
-	strb r0, [r2]
-_081DEBF8:
-	ldrb r0, [r4, 0x4]
-	adds r0, 0x8
-	mov r8, r0
-	ldrb r0, [r4, 0x1E]
-	cmp r0, 0
-	beq _081DEC06
-	movs r0, 0x40
-_081DEC06:
-	strb r0, [r4, 0x1A]
-_081DEC08:
-	ldrb r1, [r4, 0x4]
-	movs r2, 0
-	strb r1, [r4, 0xB]
-	movs r0, 0xFF
-	ands r0, r1
-	adds r1, r6, 0x1
-	mov r10, r1
-	movs r1, 0x40
-	adds r1, r4
-	mov r9, r1
-	cmp r0, 0
-	bne _081DEC22
-	b _081DED5E
-_081DEC22:
-	strb r2, [r4, 0x9]
-	b _081DED8C
-_081DEC26:
-	movs r0, 0x4
-	ands r0, r2
-	cmp r0, 0
-	beq _081DEC58
-	ldrb r0, [r4, 0xD]
-	subs r0, 0x1
-	strb r0, [r4, 0xD]
-	movs r2, 0xFF
-	ands r0, r2
-	lsls r0, 24
-	adds r1, r6, 0x1
-	mov r10, r1
-	movs r2, 0x40
-	adds r2, r4
-	mov r9, r2
-	cmp r0, 0
-	ble _081DEC4A
-	b _081DED9E
-_081DEC4A:
-	lsls r0, r6, 24
-	lsrs r0, 24
-	bl CgbOscOff
-	movs r0, 0
-	strb r0, [r4]
-	b _081DEE9C
-_081DEC58:
-	movs r0, 0x40
-	ands r0, r1
-	adds r2, r6, 0x1
-	mov r10, r2
-	movs r2, 0x40
-	adds r2, r4
-	mov r9, r2
-	cmp r0, 0
-	beq _081DEC98
-	movs r0, 0x3
-	ands r0, r1
-	cmp r0, 0
-	beq _081DEC98
-	movs r0, 0xFC
-	ands r0, r1
-	movs r2, 0
-	strb r0, [r4]
-	ldrb r1, [r4, 0x7]
-	strb r1, [r4, 0xB]
-	movs r0, 0xFF
-	ands r0, r1
-	cmp r0, 0
-	beq _081DECCA
-	movs r0, 0x1
-	ldrb r1, [r4, 0x1D]
-	orrs r0, r1
-	strb r0, [r4, 0x1D]
-	cmp r6, 0x3
-	beq _081DED8C
-	ldrb r2, [r4, 0x7]
-	mov r8, r2
-	b _081DED8C
-_081DEC98:
-	ldrb r0, [r4, 0xB]
-	cmp r0, 0
-	bne _081DED8C
-	cmp r6, 0x3
-	bne _081DECAA
-	movs r0, 0x1
-	ldrb r1, [r4, 0x1D]
-	orrs r0, r1
-	strb r0, [r4, 0x1D]
-_081DECAA:
-	adds r0, r4, 0
-	bl CgbModVol
-	movs r0, 0x3
-	ldrb r2, [r4]
-	ands r0, r2
-	cmp r0, 0
-	bne _081DECFE
-	ldrb r0, [r4, 0x9]
-	subs r0, 0x1
-	strb r0, [r4, 0x9]
-	movs r1, 0xFF
-	ands r0, r1
-	lsls r0, 24
-	cmp r0, 0
-	bgt _081DECFA
-_081DECCA:
-	ldrb r2, [r4, 0xC]
-	ldrb r1, [r4, 0xA]
-	adds r0, r2, 0
-	muls r0, r1
-	adds r0, 0xFF
-	asrs r0, 8
-	movs r1, 0
-	strb r0, [r4, 0x9]
-	lsls r0, 24
-	cmp r0, 0
-	beq _081DEC4A
-	movs r0, 0x4
-	ldrb r2, [r4]
-	orrs r0, r2
-	strb r0, [r4]
-	movs r0, 0x1
-	ldrb r1, [r4, 0x1D]
-	orrs r0, r1
-	strb r0, [r4, 0x1D]
-	cmp r6, 0x3
-	beq _081DED9E
-	movs r2, 0x8
-	mov r8, r2
-	b _081DED9E
-_081DECFA:
-	ldrb r0, [r4, 0x7]
-	b _081DED8A
-_081DECFE:
-	cmp r0, 0x1
-	bne _081DED0A
-_081DED02:
-	ldrb r0, [r4, 0x19]
-	strb r0, [r4, 0x9]
-	movs r0, 0x7
-	b _081DED8A
-_081DED0A:
-	cmp r0, 0x2
-	bne _081DED4E
-	ldrb r0, [r4, 0x9]
-	subs r0, 0x1
-	strb r0, [r4, 0x9]
-	movs r1, 0xFF
-	ands r0, r1
-	lsls r0, 24
-	ldrb r2, [r4, 0x19]
-	lsls r1, r2, 24
-	cmp r0, r1
-	bgt _081DED4A
-_081DED22:
-	ldrb r0, [r4, 0x6]
-	cmp r0, 0
-	bne _081DED32
-	movs r0, 0xFC
-	ldrb r1, [r4]
-	ands r0, r1
-	strb r0, [r4]
-	b _081DECCA
-_081DED32:
-	ldrb r0, [r4]
-	subs r0, 0x1
-	strb r0, [r4]
-	movs r0, 0x1
-	ldrb r2, [r4, 0x1D]
-	orrs r0, r2
-	strb r0, [r4, 0x1D]
-	cmp r6, 0x3
-	beq _081DED02
-	movs r0, 0x8
-	mov r8, r0
-	b _081DED02
-_081DED4A:
-	ldrb r0, [r4, 0x5]
-	b _081DED8A
-_081DED4E:
-	ldrb r0, [r4, 0x9]
-	adds r0, 0x1
-	strb r0, [r4, 0x9]
-	movs r1, 0xFF
-	ands r0, r1
-	ldrb r2, [r4, 0xA]
-	cmp r0, r2
-	bcc _081DED88
-_081DED5E:
-	ldrb r0, [r4]
-	subs r0, 0x1
-	movs r2, 0
-	strb r0, [r4]
-	ldrb r1, [r4, 0x5]
-	strb r1, [r4, 0xB]
-	movs r0, 0xFF
-	ands r0, r1
-	cmp r0, 0
-	beq _081DED22
-	movs r0, 0x1
-	ldrb r1, [r4, 0x1D]
-	orrs r0, r1
-	strb r0, [r4, 0x1D]
-	ldrb r0, [r4, 0xA]
-	strb r0, [r4, 0x9]
-	cmp r6, 0x3
-	beq _081DED8C
-	ldrb r2, [r4, 0x5]
-	mov r8, r2
-	b _081DED8C
-_081DED88:
-	ldrb r0, [r4, 0x4]
-_081DED8A:
-	strb r0, [r4, 0xB]
-_081DED8C:
-	ldrb r0, [r4, 0xB]
-	subs r0, 0x1
-	strb r0, [r4, 0xB]
-	ldr r0, [sp]
-	cmp r0, 0
-	bne _081DED9E
-	subs r0, 0x1
-	str r0, [sp]
-	b _081DEC98
-_081DED9E:
-	movs r0, 0x2
-	ldrb r1, [r4, 0x1D]
-	ands r0, r1
-	cmp r0, 0
-	beq _081DEE16
-	cmp r6, 0x3
-	bgt _081DEDDE
-	movs r0, 0x8
-	ldrb r2, [r4, 0x1]
-	ands r0, r2
-	cmp r0, 0
-	beq _081DEDDE
-	ldr r0, =REG_SOUNDBIAS + 1
-	ldrb r0, [r0]
-	cmp r0, 0x3F
-	bgt _081DEDD0
-	ldr r0, [r4, 0x20]
-	adds r0, 0x2
-	ldr r1, =0x000007fc
-	b _081DEDDA
-	.pool
-_081DEDD0:
-	cmp r0, 0x7F
-	bgt _081DEDDE
-	ldr r0, [r4, 0x20]
-	adds r0, 0x1
-	ldr r1, =0x000007fe
-_081DEDDA:
-	ands r0, r1
-	str r0, [r4, 0x20]
-_081DEDDE:
-	cmp r6, 0x4
-	beq _081DEDF0
-	ldr r0, [r4, 0x20]
-	ldr r1, [sp, 0x10]
-	strb r0, [r1]
-	b _081DEDFE
-	.pool
-_081DEDF0:
-	ldr r2, [sp, 0x10]
-	ldrb r0, [r2]
-	movs r1, 0x8
-	ands r1, r0
-	ldr r0, [r4, 0x20]
-	orrs r0, r1
-	strb r0, [r2]
-_081DEDFE:
-	movs r0, 0xC0
-	ldrb r1, [r4, 0x1A]
-	ands r0, r1
-	adds r1, r4, 0
-	adds r1, 0x21
-	ldrb r1, [r1]
-	adds r0, r1, r0
-	strb r0, [r4, 0x1A]
-	movs r2, 0xFF
-	ands r0, r2
-	ldr r1, [sp, 0x14]
-	strb r0, [r1]
-_081DEE16:
-	movs r0, 0x1
-	ldrb r2, [r4, 0x1D]
-	ands r0, r2
-	cmp r0, 0
-	beq _081DEE9C
-	ldr r1, =REG_NR51
-	ldrb r0, [r1]
-	ldrb r2, [r4, 0x1C]
-	bics r0, r2
-	ldrb r2, [r4, 0x1B]
-	orrs r0, r2
-	strb r0, [r1]
-	cmp r6, 0x3
-	bne _081DEE68
-	ldr r0, =gCgb3Vol
-	ldrb r1, [r4, 0x9]
-	adds r0, r1, r0
-	ldrb r0, [r0]
-	ldr r2, [sp, 0xC]
-	strb r0, [r2]
-	movs r1, 0x80
-	adds r0, r1, 0
-	ldrb r2, [r4, 0x1A]
-	ands r0, r2
-	cmp r0, 0
-	beq _081DEE9C
-	ldr r0, [sp, 0x8]
-	strb r1, [r0]
-	ldrb r0, [r4, 0x1A]
-	ldr r1, [sp, 0x14]
-	strb r0, [r1]
-	movs r0, 0x7F
-	ldrb r2, [r4, 0x1A]
-	ands r0, r2
-	strb r0, [r4, 0x1A]
-	b _081DEE9C
-	.pool
-_081DEE68:
-	movs r0, 0xF
-	mov r1, r8
-	ands r1, r0
-	mov r8, r1
-	ldrb r2, [r4, 0x9]
-	lsls r0, r2, 4
-	add r0, r8
-	ldr r1, [sp, 0xC]
-	strb r0, [r1]
-	movs r2, 0x80
-	ldrb r0, [r4, 0x1A]
-	orrs r0, r2
-	ldr r1, [sp, 0x14]
-	strb r0, [r1]
-	cmp r6, 0x1
-	bne _081DEE9C
-	ldr r0, [sp, 0x8]
-	ldrb r1, [r0]
-	movs r0, 0x8
-	ands r0, r1
-	cmp r0, 0
-	bne _081DEE9C
-	ldrb r0, [r4, 0x1A]
-	orrs r0, r2
-	ldr r1, [sp, 0x14]
-	strb r0, [r1]
-_081DEE9C:
-	movs r0, 0
-	strb r0, [r4, 0x1D]
-_081DEEA0:
-	mov r6, r10
-	mov r4, r9
-	cmp r6, 0x4
-	bgt _081DEEAA
-	b _081DEAA0
-_081DEEAA:
-	add sp, 0x1C
-	pop {r3-r5}
-	mov r8, r3
-	mov r9, r4
-	mov r10, r5
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	thumb_func_end CgbSound
-
-	.align 2, 0 @ Don't pad with nop.
diff --git a/include/gba/m4a_internal.h b/include/gba/m4a_internal.h
index 339a0774e..e2836c6f6 100644
--- a/include/gba/m4a_internal.h
+++ b/include/gba/m4a_internal.h
@@ -69,38 +69,38 @@ struct ToneData
 
 struct CgbChannel
 {
-    u8 sf;
-    u8 ty;
-    u8 rightVolume;
-    u8 leftVolume;
-    u8 at;
-    u8 de;
-    u8 su;
-    u8 re;
-    u8 ky;
-    u8 ev;
-    u8 eg;
-    u8 ec;
-    u8 echoVolume;
-    u8 echoLength;
-    u8 d1;
-    u8 d2;
-    u8 gt;
-    u8 mk;
-    u8 ve;
-    u8 pr;
-    u8 rp;
-    u8 d3[3];
-    u8 d5;
-    u8 sg;
-    u8 n4;
-    u8 pan;
-    u8 panMask;
-    u8 mo;
-    u8 le;
-    u8 sw;
-    u32 fr;
-    u32 wp;
+    u8 sf; // 0x0
+    u8 ty; // 0x1
+    u8 rightVolume; // 0x2
+    u8 leftVolume; // 0x3
+    u8 at; // 0x4
+    u8 de; // 0x5
+    u8 su; // 0x6
+    u8 re; // 0x7
+    u8 ky; // 0x8
+    u8 ev; // 0x9
+    u8 eg; // 0xA
+    u8 ec; // 0xB
+    u8 echoVolume; // 0xC
+    u8 echoLength; // 0xD
+    u8 d1; // 0xE
+    u8 d2; // 0xF
+    u8 gt; // 0x10
+    u8 mk; // 0x11
+    u8 ve; // 0x12
+    u8 pr; // 0x13
+    u8 rp; // 0x14
+    u8 d3[3]; // 0x15, 0x16, 0x17
+    u8 d5; // 0x18
+    u8 sg; // 0x19
+    u8 n4; // 0x1A
+    u8 pan; // 0x1B
+    u8 panMask; // 0x1C
+    u8 mo; // 0x1D
+    u8 le; // 0x1E
+    u8 sw; // 0x1F
+    u32 fr; // 0x20
+    u32 *wp;
     u32 cp;
     u32 tp;
     u32 pp;
@@ -397,6 +397,7 @@ void m4aSoundMode(u32 mode);
 void MPlayOpen(struct MusicPlayerInfo *mplayInfo, struct MusicPlayerTrack *track, u8 a3);
 void CgbSound(void);
 void CgbOscOff(u8);
+void CgbModVol(struct CgbChannel *chan);
 u32 MidiKeyToCgbFreq(u8, u8, u8);
 void DummyFunc(void);
 void MPlayJumpTableCopy(void **mplayJumpTable);
diff --git a/ld_script.txt b/ld_script.txt
index caac5c0bd..d1219cb3e 100644
--- a/ld_script.txt
+++ b/ld_script.txt
@@ -320,7 +320,7 @@ SECTIONS {
         asm/libgcnmultiboot.o(.text);
         asm/m4a_1.o(.text);
         src/m4a_2.o(.text);
-        asm/m4a_3.o(.text);
+        src/m4a_3.o(.text);
         src/m4a_4.o(.text);
         src/agb_flash.o(.text);
         src/agb_flash_1m.o(.text);
diff --git a/src/m4a_3.c b/src/m4a_3.c
new file mode 100644
index 000000000..77d0087c0
--- /dev/null
+++ b/src/m4a_3.c
@@ -0,0 +1,324 @@
+#include "gba/m4a_internal.h"
+
+extern const u8 gCgb3Vol[];
+
+void CgbSound(void)
+{
+    s32 ch;
+    struct CgbChannel *channels;
+    s32 evAdd;
+    s32 prevC15;
+    struct SoundInfo *soundInfo = SOUND_INFO_PTR;
+    vu8 *nrx0ptr;
+    vu8 *nrx1ptr;
+    vu8 *nrx2ptr;
+    vu8 *nrx3ptr;
+    vu8 *nrx4ptr;
+
+    // Most comparision operations that cast to s8 perform 'and' by 0xFF.
+    int xFF = 0xff;
+
+    if (soundInfo->c15)
+        soundInfo->c15--;
+    else
+        soundInfo->c15 = 14;
+
+    for (ch = 1, channels = soundInfo->cgbChans; ch <= 4; ch++, channels++)
+    {
+        if (!(channels->sf & 0xc7))
+            continue;
+
+        switch (ch)
+        {
+        case 1:
+            nrx0ptr = (vu8 *)(REG_ADDR_NR10);
+            nrx1ptr = (vu8 *)(REG_ADDR_NR11);
+            nrx2ptr = (vu8 *)(REG_ADDR_NR12);
+            nrx3ptr = (vu8 *)(REG_ADDR_NR13);
+            nrx4ptr = (vu8 *)(REG_ADDR_NR14);
+            break;
+        case 2:
+            nrx0ptr = (vu8 *)(REG_ADDR_NR10+1);
+            nrx1ptr = (vu8 *)(REG_ADDR_NR21);
+            nrx2ptr = (vu8 *)(REG_ADDR_NR22);
+            nrx3ptr = (vu8 *)(REG_ADDR_NR23);
+            nrx4ptr = (vu8 *)(REG_ADDR_NR24);
+            break;
+        case 3:
+            nrx0ptr = (vu8 *)(REG_ADDR_NR30);
+            nrx1ptr = (vu8 *)(REG_ADDR_NR31);
+            nrx2ptr = (vu8 *)(REG_ADDR_NR32);
+            nrx3ptr = (vu8 *)(REG_ADDR_NR33);
+            nrx4ptr = (vu8 *)(REG_ADDR_NR34);
+            break;
+        default:
+            nrx0ptr = (vu8 *)(REG_ADDR_NR30+1);
+            nrx1ptr = (vu8 *)(REG_ADDR_NR41);
+            nrx2ptr = (vu8 *)(REG_ADDR_NR42);
+            nrx3ptr = (vu8 *)(REG_ADDR_NR43);
+            nrx4ptr = (vu8 *)(REG_ADDR_NR44);
+            break;
+        }
+
+        prevC15 = soundInfo->c15;
+        evAdd = *nrx2ptr;
+
+        if (channels->sf & 0x80)
+        {
+            if (!(channels->sf & 0x40))
+            {
+                channels->sf = 3;
+                channels->mo = 3;
+                CgbModVol(channels);
+                switch (ch)
+                {
+                case 1:
+                    *nrx0ptr = channels->sw;
+                    // fallthrough
+                case 2:
+                    *nrx1ptr = ((u32)channels->wp << 6) + channels->le;
+                    goto loc_82E0E30;
+                    break;
+                case 3:
+                    if ((u32)channels->wp != channels->cp)
+                    {
+                        *nrx0ptr = 0x40;
+                        REG_WAVE_RAM0 = channels->wp[0];
+                        REG_WAVE_RAM1 = channels->wp[1];
+                        REG_WAVE_RAM2 = channels->wp[2];
+                        REG_WAVE_RAM3 = channels->wp[3];
+                        channels->cp = (u32)channels->wp;
+                    }
+                    *nrx0ptr = 0;
+                    *nrx1ptr = channels->le;
+                    if (channels->le)
+                        channels->n4 = -64;
+                    else
+                        channels->n4 = -128;
+                    break;
+                default:
+                    *nrx1ptr = channels->le;
+                    *nrx3ptr = (u32)channels->wp << 3;
+                loc_82E0E30:
+                    evAdd = channels->at + 8;
+                    if (channels->le)
+                        channels->n4 = 64;
+                    else
+                        channels->n4 = 0;
+                    break;
+                }
+                channels->ec = channels->at;
+                if ((s8)(channels->at & xFF))
+                {
+                    channels->ev = 0;
+                    goto EC_MINUS;
+                }
+                else
+                {
+                    goto loc_82E0F96;
+                }
+            }
+            else
+            {
+                goto loc_82E0E82;
+            }
+        }
+        else if (channels->sf & 0x04)
+        {
+            channels->echoLength--;
+            if ((s8)(channels->echoLength & xFF) <= 0)
+            {
+            loc_82E0E82:
+                CgbOscOff(ch);
+                channels->sf = 0;
+                goto LAST_LABEL;
+            }
+            goto loc_82E0FD6;
+        }
+        else if ((channels->sf & 0x40) && (channels->sf & 0x03))
+        {
+            channels->sf &= 0xfc;
+            channels->ec = channels->re;
+            if ((s8)(channels->re & xFF))
+            {
+                channels->mo |= 1;
+                if (ch != 3)
+                {
+                    evAdd = channels->re;
+                }
+                goto EC_MINUS;
+            }
+            else
+            {
+                goto loc_82E0F02;
+            }
+        }
+        else
+        {
+        loc_82E0ED0:
+            if (channels->ec == 0)
+            {
+                if (ch == 3)
+                {
+                    channels->mo |= 1;
+                }
+                CgbModVol(channels);
+                if ((channels->sf & 0x3) == 0)
+                {
+                    channels->ev--;
+                    if ((s8)(channels->ev & xFF) <= 0)
+                    {
+                    loc_82E0F02:
+                        channels->ev = ((channels->eg * channels->echoVolume) + 0xFF) >> 8;
+                        if (channels->ev)
+                        {
+                            channels->sf |= 0x4;
+                            channels->mo |= 1;
+                            if (ch != 3)
+                            {
+                                evAdd = 8;
+                            }
+                            goto loc_82E0FD6;
+                        }
+                        else
+                        {
+                            goto loc_82E0E82;
+                        }
+                    }
+                    else
+                    {
+                        channels->ec = channels->re;
+                    }
+                }
+                else if ((channels->sf & 0x3) == 1)
+                {
+                loc_82E0F3A:
+                    channels->ev = channels->sg;
+                    channels->ec = 7;
+                }
+                else if ((channels->sf & 0x3) == 2)
+                {
+                    int ev, sg;
+
+                    channels->ev--;
+                    ev = (s8)(channels->ev & xFF);
+                    sg = (s8)(channels->sg);
+                    if (ev <= sg)
+                    {
+                    loc_82E0F5A:
+                        if (channels->su == 0)
+                        {
+                            channels->sf &= 0xfc;
+                            goto loc_82E0F02;
+                        }
+                        else
+                        {
+                            channels->sf--;
+                            channels->mo |= 1;
+                            if (ch != 3)
+                            {
+                                evAdd = 8;
+                            }
+                            goto loc_82E0F3A;
+                        }
+                    }
+                    else
+                    {
+                        channels->ec = channels->de;
+                    }
+                }
+                else
+                {
+                    channels->ev++;
+                    if ((u8)(channels->ev & xFF) >= channels->eg)
+                    {
+                    loc_82E0F96:
+                        channels->sf--;
+                        channels->ec = channels->de;
+                        if ((u8)(channels->ec & xFF))
+                        {
+                            channels->mo |= 1;
+                            channels->ev = channels->eg;
+                            if (ch != 3)
+                            {
+                                evAdd = channels->de;
+                            }
+                        }
+                        else
+                        {
+                            goto loc_82E0F5A;
+                        }
+                    }
+                    else
+                    {
+                        channels->ec = channels->at;
+                    }
+                }
+            }
+        }
+
+    EC_MINUS:
+        channels->ec--;
+        if (prevC15 == 0)
+        {
+            prevC15--;
+            goto loc_82E0ED0;
+        }
+
+    loc_82E0FD6:
+        if (channels->mo & 0x2)
+        {
+            if (ch < 4 && (channels->ty & 0x08))
+            {
+                int biasH = REG_SOUNDBIAS_H;
+
+                if (biasH < 64)
+                {
+                    channels->fr = (channels->fr + 2) & 0x7fc;
+                }
+                else if (biasH < 128)
+                {
+                    channels->fr = (channels->fr + 1) & 0x7fe;
+                }
+            }
+            if (ch != 4)
+            {
+                *nrx3ptr = channels->fr;
+            }
+            else
+            {
+                *nrx3ptr = (*nrx3ptr & 0x08) | channels->fr;
+            }
+            channels->n4 = (channels->n4 & 0xC0) + (*((u8*)(&channels->fr) + 1));
+            *nrx4ptr = (s8)(channels->n4 & xFF);
+        }
+
+        if (channels->mo & 1)
+        {
+            REG_NR51 = (REG_NR51 & ~channels->panMask) | channels->pan;
+            if (ch == 3)
+            {
+                *nrx2ptr = gCgb3Vol[channels->ev];
+                if (channels->n4 & 0x80)
+                {
+                    *nrx0ptr = 0x80;
+                    *nrx4ptr = channels->n4;
+                    channels->n4 &= 0x7f;
+                }
+            }
+            else
+            {
+                evAdd &= 0xf;
+                *nrx2ptr = (channels->ev << 4) + evAdd;
+                *nrx4ptr = channels->n4 | 0x80;
+                if (ch == 1 && !(*nrx0ptr & 0x08))
+                {
+                    *nrx4ptr = channels->n4 | 0x80;
+                }
+            }
+        }
+
+    LAST_LABEL:
+        channels->mo = 0;
+    }
+}