diff --git a/source/Cosmos.Hardware.PC/Bus/CPUBus.cs b/source/Cosmos.Hardware.PC/Bus/CPUBus.cs
index 48452e4d8..e6ab576bb 100644
--- a/source/Cosmos.Hardware.PC/Bus/CPUBus.cs
+++ b/source/Cosmos.Hardware.PC/Bus/CPUBus.cs
@@ -8,10 +8,14 @@ namespace Cosmos.Hardware.PC.Bus {
         // These are public. Would prefer internal, but will cause issues
         // in future as we add devices from other assemblies.
         // What else can we do to restrict access to them?
+        //
+        // all plugs
         public static void Write8(UInt16 aPort, byte aData) { }
         public static void Write16(UInt16 aPort, UInt16 aData) { }
+        public static void Write32(UInt16 aPort, UInt32 aData) { }
 
         public static byte Read8(UInt16 aPort) { return 0; }
         public static UInt16 Read16(UInt16 aPort) { return 0; }
+        public static UInt32 Read32(UInt16 aPort) { return 0; }
     }
 }