From ae963b54437380bc94c7716857ea6af8a5ec3ea7 Mon Sep 17 00:00:00 2001
From: goyuken <goyuken@4bbf4f03-6f44-549e-7e59-35d4b0962838>
Date: Mon, 3 Dec 2012 15:01:04 +0000
Subject: [PATCH] nes: fix PAL DMC frequencies

---
 BizHawk.Emulation/Consoles/Nintendo/NES/APU.cs  | 13 ++++++++-----
 BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs |  5 ++++-
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/BizHawk.Emulation/Consoles/Nintendo/NES/APU.cs b/BizHawk.Emulation/Consoles/Nintendo/NES/APU.cs
index 8c35f9de55..a6cf49d482 100644
--- a/BizHawk.Emulation/Consoles/Nintendo/NES/APU.cs
+++ b/BizHawk.Emulation/Consoles/Nintendo/NES/APU.cs
@@ -34,10 +34,10 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 			public bool EnableDMC = true;
 
 			NES nes;
-			public APU(NES nes, APU old = null)
+			public APU(NES nes, APU old, bool pal)
 			{
 				this.nes = nes;
-				dmc = new DMCUnit(this);
+				dmc = new DMCUnit(this, pal);
 				if (old != null)
 				{
 					EnableSquare1 = old.EnableSquare1;
@@ -49,6 +49,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 			}
 
 			static int[] DMC_RATE_NTSC = { 428, 380, 340, 320, 286, 254, 226, 214, 190, 160, 142, 128, 106, 84, 72, 54 };
+			static int[] DMC_RATE_PAL = { 398, 354, 316, 298, 276, 236, 210, 198, 176, 148, 132, 118, 98, 78, 66, 50 };
 			static int[] LENGTH_TABLE = { 10, 254, 20, 2, 40, 4, 80, 6, 160, 8, 60, 10, 14, 12, 26, 14, 12, 16, 24, 18, 48, 20, 96, 22, 192, 24, 72, 26, 16, 28, 32, 30 };
 			static byte[,] PULSE_DUTY = {
 				{0,1,0,0,0,0,0,0}, //(12.5%)
@@ -548,11 +549,13 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 			class DMCUnit
 			{
 				APU apu;
-				public DMCUnit(APU apu)
+				int[] DMC_RATE;
+				public DMCUnit(APU apu, bool pal)
 				{
 					this.apu = apu;
 					out_silence = true;
-					timer_reload = DMC_RATE_NTSC[0];
+					DMC_RATE = pal ? DMC_RATE_PAL : DMC_RATE_NTSC;
+					timer_reload = DMC_RATE[0];
 					sample_buffer_filled = false;
 					out_deltacounter = 64;
 					out_bits_remaining = 0;
@@ -700,7 +703,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 						case 0:
 							irq_enabled = val.Bit(7);
 							loop_flag = val.Bit(6);
-							timer_reload = DMC_RATE_NTSC[val & 0xF];
+							timer_reload = DMC_RATE[val & 0xF];
 							if (!irq_enabled) apu.dmc_irq = false;
 							apu.SyncIRQ();
 							break;
diff --git a/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs b/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs
index 773255a299..18b52d891d 100644
--- a/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs
+++ b/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs
@@ -139,7 +139,6 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 
 			BoardSystemHardReset();
 
-			apu = new APU(this, apu);
 			// don't replace the magicSoundProvider on reset, as it's not needed
 			// if (magicSoundProvider != null) magicSoundProvider.Dispose();
 
@@ -150,6 +149,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 				case "NES-PAL":
 				case "NES-PAL-A":
 				case "NES-PAL-B":
+					apu = new APU(this, apu, true);
 					ppu.region = PPU.Region.PAL;
 					CoreOutputComm.VsyncNum = 50;
 					CoreOutputComm.VsyncDen = 1;
@@ -159,6 +159,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 					break;
 				case "NES-NTSC":
 				case "Famicom":
+					apu = new APU(this, apu, false);
 					ppu.region = PPU.Region.NTSC;
 					cpu_sequence = cpu_sequence_NTSC;
 					if (magicSoundProvider == null)
@@ -167,6 +168,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 				// there's no official name for these in bootgod, not sure what we should use
 				//case "PC10"://TODO
 				case "VS":
+					apu = new APU(this, apu, false);
 					ppu.region = PPU.Region.RGB;
 					cpu_sequence = cpu_sequence_NTSC;
 					if (magicSoundProvider == null)
@@ -175,6 +177,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 					break;
 				// this is in bootgod, but not used at all
 				case "Dendy":
+					apu = new APU(this, apu, false);
 					ppu.region = PPU.Region.Dendy;
 					CoreOutputComm.VsyncNum = 50;
 					CoreOutputComm.VsyncDen = 1;