diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/UNIF/UNIF_BMC-Ghostbusters63in1.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/UNIF/UNIF_BMC-Ghostbusters63in1.cs
index 631d6e08fd..5651c23ca7 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/UNIF/UNIF_BMC-Ghostbusters63in1.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/UNIF/UNIF_BMC-Ghostbusters63in1.cs
@@ -1,17 +1,20 @@
 using BizHawk.Common;
 using BizHawk.Common.NumberExtensions;
-
+using System;
+
 namespace BizHawk.Emulation.Cores.Nintendo.NES
 {
 	// Adapted from FCEUX src
 	public sealed class UNIF_BMC_Ghostbusters63in1 : NES.NESBoardBase
 	{
 		private ByteBuffer reg = new ByteBuffer(2);
-		private readonly int[] banks = new [] { 0, 0, 524288, 1048576 };
+		private readonly int[] banks = new [] { 0, 0, 524288, 1048576};
 		private int bank;
 
 		[MapperProp]
-		public int Ghostbusters63in1_chip;
+		public bool Ghostbusters63in1_63set=true;
+		[MapperProp]
+		public int Ghostbusters63in1_chip_22_select;
 
 		public override bool Configure(NES.EDetectionOrigin origin)
 		{
@@ -32,7 +35,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 		{
 			ser.Sync("reg", ref reg);
 			ser.Sync("bank", ref bank);
-			ser.Sync("bank", ref Ghostbusters63in1_chip);
+			ser.Sync("bank", ref Ghostbusters63in1_63set);
+			ser.Sync("bank", ref Ghostbusters63in1_chip_22_select);
 			base.SyncState(ser);
 		}
 
@@ -40,9 +44,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 		{
 			reg[addr & 1] = value;
 
-			//bank = ((reg[0] & 0x80) >> 7) | ((reg[1] & 1) << 1);
+			bank = ((reg[0] & 0x80) >> 7) | ((reg[1] & 1) << 1);
 
 			SetMirrorType(reg[0].Bit(6) ? EMirrorType.Vertical : EMirrorType.Horizontal);
+			Console.WriteLine(reg[0]);
+			Console.WriteLine(reg[1]);
 		}
 
 		public override byte ReadPRG(int addr)
@@ -53,14 +59,24 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 			//}
 
 			if (reg[0].Bit(5))
-			{
-				var offset = (Ghostbusters63in1_chip % 3) * (1024 * 512);
+			{
+				var offset=0;
+				if (Ghostbusters63in1_63set)
+					offset = banks[bank];
+				else
+					offset = banks[Ghostbusters63in1_chip_22_select];
+
 				int b = (reg[0] & 0x1F);
 				return ROM[offset + (b << 14) + (addr & 0x3FFF)];
 			}
 			else
-			{
-				var offset = (Ghostbusters63in1_chip % 3) * (1024 * 512);
+			{
+				var offset = 0;
+				if (Ghostbusters63in1_63set)
+					offset = banks[bank];
+				else
+					offset = banks[Ghostbusters63in1_chip_22_select];
+
 				int b = ((reg[0] >> 1) & 0x0F);
 				return ROM[offset + (b << 15) + addr];
 			}