diff --git a/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs b/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs
index 90449b4578..a033f081b7 100644
--- a/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs
+++ b/BizHawk.Emulation/Consoles/Nintendo/NES/Core.cs
@@ -286,15 +286,34 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 
 		public void WriteMemory(ushort addr, byte value)
 		{
-			if (addr < 0x0800) ram[addr] = value;
-			else if (addr < 0x1000) ram[addr - 0x0800] = value;
-			else if (addr < 0x1800) ram[addr - 0x1000] = value;
-			else if (addr < 0x2000) ram[addr - 0x1800] = value;
-			else if (addr < 0x4000) ppu.WriteReg(addr & 7, value);
-			else if (addr < 0x4020) WriteReg(addr, value);  //we're not rebasing the register just to keep register names canonical
-			else if (addr < 0x6000) board.WriteEXP(addr - 0x4000, value); 
-			else if (addr < 0x8000) board.WriteWRAM(addr - 0x6000, value);
-			else board.WritePRG(addr - 0x8000, value);
+			if (addr < 0x0800)
+			{
+				ram[addr] = value;
+			}
+			else if (addr < 0x2000)
+			{
+				ram[addr & 0x7FF] = value;
+			}
+			else if (addr < 0x4000)
+			{
+				ppu.WriteReg(addr & 7, value);
+			}
+			else if (addr < 0x4020)
+			{
+				WriteReg(addr, value);  //we're not rebasing the register just to keep register names canonical
+			}
+			else if (addr < 0x6000)
+			{
+				board.WriteEXP(addr - 0x4000, value);
+			}
+			else if (addr < 0x8000)
+			{
+				board.WriteWRAM(addr - 0x6000, value);
+			}
+			else
+			{
+				board.WritePRG(addr - 0x8000, value);
+			}
 		}
 
 	}