diff --git a/BizHawk.Emulation/Interfaces/CoreComms.cs b/BizHawk.Emulation/Interfaces/CoreComms.cs
index 2bbde2a4aa..3faaeece7b 100644
--- a/BizHawk.Emulation/Interfaces/CoreComms.cs
+++ b/BizHawk.Emulation/Interfaces/CoreComms.cs
@@ -99,8 +99,8 @@ namespace BizHawk
 	public class MemoryCallbackSystem
 	{
 		public int? ReadAddr = null;
-		private System.Action ReadCallback = null;
-		public void SetReadCallback(System.Action func)
+		private System.Action<uint> ReadCallback = null;
+		public void SetReadCallback(System.Action<uint> func)
 		{
 			ReadCallback = func;
 		}
@@ -121,19 +121,19 @@ namespace BizHawk
 				{
 					if (ReadAddr == addr)
 					{
-						ReadCallback();
+						ReadCallback((uint)addr);
 					}
 				}
 				else
 				{
-					ReadCallback();
+					ReadCallback((uint)addr);
 				}
 			}
 		}
 
 		public int? WriteAddr = null;
-		private System.Action WriteCallback = null;
-		public void SetWriteCallback(System.Action func)
+		private System.Action<uint> WriteCallback = null;
+		public void SetWriteCallback(System.Action<uint> func)
 		{
 			WriteCallback = func;
 		}
@@ -154,12 +154,12 @@ namespace BizHawk
 				{
 					if (WriteAddr == addr)
 					{
-						WriteCallback();
+						WriteCallback((uint)addr);
 					}
 				}
 				else
 				{
-					WriteCallback();
+					WriteCallback((uint)addr);
 				}
 			}
 		}
diff --git a/BizHawk.MultiClient/LuaImplementation.cs b/BizHawk.MultiClient/LuaImplementation.cs
index d4d8265ffc..a6e58549a6 100644
--- a/BizHawk.MultiClient/LuaImplementation.cs
+++ b/BizHawk.MultiClient/LuaImplementation.cs
@@ -2698,11 +2698,11 @@ namespace BizHawk.MultiClient
 				}
 
 				Global.Emulator.CoreInputComm.MemoryCallbackSystem.ReadAddr = _addr;
-				Global.Emulator.CoreInputComm.MemoryCallbackSystem.SetReadCallback(delegate()
+				Global.Emulator.CoreInputComm.MemoryCallbackSystem.SetReadCallback(delegate(uint addr)
 				{
 					try
 					{
-						luaf.Call();
+						luaf.Call(addr);
 					}
 					catch (SystemException e)
 					{
@@ -2736,11 +2736,11 @@ namespace BizHawk.MultiClient
 				}
 
 				Global.Emulator.CoreInputComm.MemoryCallbackSystem.WriteAddr = _addr;
-				Global.Emulator.CoreInputComm.MemoryCallbackSystem.SetWriteCallback(delegate()
+				Global.Emulator.CoreInputComm.MemoryCallbackSystem.SetWriteCallback(delegate(uint addr)
 				{
 					try
 					{
-						luaf.Call();
+						luaf.Call(addr);
 					}
 					catch (SystemException e)
 					{