From 90a288afebe6646aa97de0419783a624b289692c Mon Sep 17 00:00:00 2001
From: adelikat <adelikat@tasvideos.org>
Date: Fri, 19 Oct 2012 23:31:42 +0000
Subject: [PATCH] Implement X07 mapper

---
 .../Consoles/Atari/2600/Mappers/mX07.cs       | 44 +++++++++++++++++++
 .../output/gamedb/gamedb_a2600.txt            |  3 +-
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs
index c88dd38ffa..5ca578d2fe 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs
@@ -38,6 +38,50 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 
 	class mX07 : MapperBase
 	{
+		int rombank_2k = 0;
 
+		public override byte ReadMemory(ushort addr)
+		{
+			Address(addr);
+			if (addr < 0x1000)
+			{
+				return base.ReadMemory(addr);
+			}
+			else
+			{
+				return core.rom[(rombank_2k << 12) + (addr & 0xFFF)];
+			}
+		}
+		public override void WriteMemory(ushort addr, byte value)
+		{
+			Address(addr);
+			if (addr < 0x1000) base.WriteMemory(addr, value);
+		}
+
+		public override void SyncState(Serializer ser)
+		{
+			base.SyncState(ser);
+			ser.Sync("rombank_2k", ref rombank_2k);
+		}
+
+		void Address(ushort addr)
+		{
+			if ((addr & 0x180F) == 0x080D)
+			{
+				bank((addr & 0xF0) >> 4);
+			}
+			else if ((addr & 0x1880) == 0)
+			{
+				if ((rombank_2k & 0xE) == 0xE)
+				{
+					bank(((addr & 0x40) >> 6) | (rombank_2k & 0xE));
+				}
+			}
+		}
+
+		private void bank(int bank)
+		{
+			rombank_2k = (bank & 0x0F);
+		}
 	}
 }
diff --git a/BizHawk.MultiClient/output/gamedb/gamedb_a2600.txt b/BizHawk.MultiClient/output/gamedb/gamedb_a2600.txt
index 51cf26c923..cdf98252e4 100644
--- a/BizHawk.MultiClient/output/gamedb/gamedb_a2600.txt
+++ b/BizHawk.MultiClient/output/gamedb/gamedb_a2600.txt
@@ -2689,4 +2689,5 @@ sha1:feb6bd37e5d722bd080433587972b980afff5fa5		Zoo Fun (HomeVision)	A26		m=4K
 sha1:e9cbd1348c7c2e6f7a1ed174554fc144f291debc		Ko Avgn - Ntsc - 2009-08-16	A26		m=F4
 sha1:080deaf5fe7c0e3b132365bfe9e8003becf3498d		Ko Avgn - Ntsc - 2009-08-16	A26		m=F4
 sha1:63C12146C183BCCBF05C0044A961DC40790E3212		Pleiades (1983) (UA Limited) (Prototype)	A26		m=UA
-sha1:86BBE6E62DACF6E5CD771BD9249C4ED51BF60092		dungeon_rc4	A26		m=F4
\ No newline at end of file
+sha1:86BBE6E62DACF6E5CD771BD9249C4ED51BF60092		dungeon_rc4	A26		m=F4
+sha1:C11F59AE0ECD376AF52AE57B5BE8B6F039DE0D0E		MegaBoy (X07 Bankswitching Conversion) (2008) (Fred Quimby)	A26		m=X07
\ No newline at end of file