From 92f18928fbe1ce8402b3634d1d94fd4865548448 Mon Sep 17 00:00:00 2001
From: adelikat <adelikat@tasvideos.org>
Date: Fri, 16 Sep 2016 11:28:56 -0400
Subject: [PATCH] Implement Mapper238/UNIF_UNL-603-5052

---
 .../BizHawk.Emulation.Cores.csproj            |  1 +
 .../NES/Boards/MMC3_family/Mapper238.cs       | 60 +++++++++++++++++++
 2 files changed, 61 insertions(+)
 create mode 100644 BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/MMC3_family/Mapper238.cs

diff --git a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
index fa25dec28c..db6cb5cb44 100644
--- a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
+++ b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
@@ -684,6 +684,7 @@
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper197.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper205.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper219.cs" />
+    <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper238.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper245.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper249.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper250.cs" />
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/MMC3_family/Mapper238.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/MMC3_family/Mapper238.cs
new file mode 100644
index 0000000000..3a968dcc5e
--- /dev/null
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/MMC3_family/Mapper238.cs
@@ -0,0 +1,60 @@
+using BizHawk.Common;
+
+namespace BizHawk.Emulation.Cores.Nintendo.NES
+{
+	// Adapted from FCEUX src
+	public sealed class Mapper238 : MMC3Board_Base
+	{
+		private readonly int[] lut = { 0x00, 0x02, 0x02, 0x03 };
+		private byte reg;
+
+		public override bool Configure(NES.EDetectionOrigin origin)
+		{
+			switch (Cart.board_type)
+			{
+				case "MAPPER238": // Nestopia suggests this board is mapper 238, I do not have any ROMs with this ines header info to confirm
+				case "UNIF_UNL-603-5052":
+					break;
+			}
+
+			BaseSetup();
+			return true;
+		}
+
+		public override void SyncState(Serializer ser)
+		{
+			base.SyncState(ser);
+			ser.Sync("reg", ref reg);
+		}
+
+		public override byte ReadEXP(int addr)
+		{
+			if (addr < 0x20)
+			{
+				return base.ReadEXP(addr);
+			}
+
+			return reg;
+		}
+
+		public override byte ReadWRAM(int addr)
+		{
+			return reg;
+		}
+
+		public override void WriteEXP(int addr, byte value)
+		{
+			if (addr < 0x20)
+			{
+				base.WriteEXP(addr, value);
+			}
+
+			reg = (byte)lut[value & 3];
+		}
+
+		public override void WriteWRAM(int addr, byte value)
+		{
+			reg = (byte)lut[value & 3];
+		}
+	}
+}