diff --git a/BizHawk.Emulation.Common/Base Implementations/CallbackBasedTraceBuffer.cs b/BizHawk.Emulation.Common/Base Implementations/CallbackBasedTraceBuffer.cs
new file mode 100644
index 0000000000..c74b98dbbb
--- /dev/null
+++ b/BizHawk.Emulation.Common/Base Implementations/CallbackBasedTraceBuffer.cs	
@@ -0,0 +1,109 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+using BizHawk.Emulation.Common.IEmulatorExtensions;
+
+namespace BizHawk.Emulation.Common
+{
+	public abstract class CallbackBasedTraceBuffer : ITraceable
+	{
+		public CallbackBasedTraceBuffer(IDebuggable debuggableCore, IMemoryDomains memoryDomains, IDisassemblable disassembler)
+		{
+			if (!debuggableCore.MemoryCallbacksAvailable())
+			{
+				throw new InvalidOperationException("Memory callbacks are required");
+			}
+
+			try
+			{
+				var dummy = debuggableCore.GetCpuFlagsAndRegisters();
+			}
+			catch (NotImplementedException)
+			{
+				throw new InvalidOperationException("GetCpuFlagsAndRegisters is required");
+			}
+
+			Header = "Instructions";
+			DebuggableCore = debuggableCore;
+			MemoryDomains = memoryDomains;
+			Disassembler = disassembler;
+		}
+
+		protected readonly IMemoryDomains MemoryDomains;
+		protected readonly IDisassemblable Disassembler;
+		protected readonly IDebuggable DebuggableCore;
+
+		protected readonly List<TraceInfo> Buffer = new List<TraceInfo>();
+
+		private bool _enabled;
+
+		public abstract void TraceFromCallback();
+
+		public bool Enabled
+		{
+			get
+			{
+				return _enabled;
+			}
+
+			set
+			{
+				_enabled = value;
+				DebuggableCore.MemoryCallbacks.Remove(TraceFromCallback);
+
+				if (_enabled)
+				{
+					DebuggableCore.MemoryCallbacks.Add(new TracingMemoryCallback(TraceFromCallback));
+				}
+			}
+		}
+
+		public string Header { get; set; }
+
+		public IEnumerable<TraceInfo> Contents
+		{
+			get { return Buffer; }
+		}
+
+		public IEnumerable<TraceInfo> TakeContents()
+		{
+			var contents = Buffer.ToList();
+			Buffer.Clear();
+			return contents;
+		}
+
+		public void Put(TraceInfo content)
+		{
+			if (Enabled)
+			{
+				Buffer.Add(content);
+			}
+		}
+
+		public class TracingMemoryCallback : IMemoryCallback
+		{
+			public TracingMemoryCallback(Action callback)
+			{
+				Callback = callback;
+			}
+
+			public MemoryCallbackType Type
+			{
+				get { return MemoryCallbackType.Execute; }
+			}
+
+			public string Name
+			{
+				get { return "Trace Logging"; }
+			}
+
+			public Action Callback { get; private set; }
+
+			public uint? Address
+			{
+				get { return null; }
+			}
+		}
+	}
+}
diff --git a/BizHawk.Emulation.Common/BizHawk.Emulation.Common.csproj b/BizHawk.Emulation.Common/BizHawk.Emulation.Common.csproj
index 4389a2effe..cfb34c0508 100644
--- a/BizHawk.Emulation.Common/BizHawk.Emulation.Common.csproj
+++ b/BizHawk.Emulation.Common/BizHawk.Emulation.Common.csproj
@@ -55,6 +55,7 @@
       <Link>VersionInfo.cs</Link>
     </Compile>
     <Compile Include="Base Implementations\BasicServiceProvider.cs" />
+    <Compile Include="Base Implementations\CallbackBasedTraceBuffer.cs" />
     <Compile Include="Base Implementations\ControllerDefinition.cs" />
     <Compile Include="Base Implementations\InputCallbackSystem.cs" />
     <Compile Include="Base Implementations\MemoryCallbackSystem.cs" />
diff --git a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
index f2fe4a4d32..41154a738b 100644
--- a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
+++ b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
@@ -817,7 +817,9 @@
     <Compile Include="Consoles\Sega\gpgx\GPGX.IStatable.cs">
       <DependentUpon>GPGX.cs</DependentUpon>
     </Compile>
-    <Compile Include="Consoles\Sega\gpgx\GPGX.ITraceable.cs" />
+    <Compile Include="Consoles\Sega\gpgx\GPGX.ITraceable.cs">
+        <DependentUpon>GPGX.cs</DependentUpon>
+    </Compile>
     <Compile Include="Consoles\Sega\gpgx\GPGX.IVideoProvider.cs">
       <DependentUpon>GPGX.cs</DependentUpon>
     </Compile>
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.ITraceable.cs b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.ITraceable.cs
index b01061faab..7b1f2d903b 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.ITraceable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.ITraceable.cs
@@ -1,9 +1,8 @@
 using BizHawk.Emulation.Common;
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Text;
-using BizHawk.Emulation.Common.IEmulatorExtensions;
+
 using BizHawk.Common.NumberExtensions;
 
 namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
@@ -12,43 +11,15 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 	{
 		private readonly ITraceable Tracer;
 
-		// TODO: move this to BaseImplementations and make the TraceFromCallback settable by the core
-		public class CallbackBasedTraceBuffer : ITraceable
+		public class GPGXTraceBuffer : CallbackBasedTraceBuffer
 		{
-			public CallbackBasedTraceBuffer(IDebuggable debuggableCore)
+			public GPGXTraceBuffer(IDebuggable debuggableCore, IMemoryDomains memoryDomains, IDisassemblable disassembler)
+				: base(debuggableCore, memoryDomains, disassembler)
 			{
-				if (!debuggableCore.MemoryCallbacksAvailable())
-				{
-					throw new InvalidOperationException("Memory callbacks are required");
-				}
-
-				try
-				{
-					var dummy = debuggableCore.GetCpuFlagsAndRegisters();
-				}
-				catch(NotImplementedException)
-				{
-					throw new InvalidOperationException("GetCpuFlagsAndRegisters is required");
-				}
-
-				Header = "Instructions";
-				DebuggableCore = debuggableCore;
-
-				// TODO: refactor
-				MemoryDomains = (debuggableCore as IEmulator).ServiceProvider.GetService<IMemoryDomains>();
-				Disassembler = (debuggableCore as IEmulator).ServiceProvider.GetService<IDisassemblable>();
+				Header = "M68K Instructions";
 			}
 
-			// TODO: think about this
-			private readonly IMemoryDomains MemoryDomains;
-			private readonly IDisassemblable Disassembler;
-			private readonly IDebuggable DebuggableCore;
-
-			private readonly List<TraceInfo> Buffer = new List<TraceInfo>();
-
-			private bool _enabled;
-
-			private void TraceFromCallback()
+			public override void TraceFromCallback()
 			{
 				var regs = DebuggableCore.GetCpuFlagsAndRegisters();
 				uint pc = (uint)regs["M68K PC"].Value;
@@ -57,7 +28,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 
 				var traceInfo = new TraceInfo
 				{
-					Disassembly = string.Format("{0:X6}:  {1,-32}", pc, disasm)
+					Disassembly = string.Format("{0:X6}:  {1}", pc, disasm)
 				};
 
 				var sb = new StringBuilder();
@@ -90,72 +61,6 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 
 				Buffer.Add(traceInfo);
 			}
-
-			public bool Enabled
-			{
-				get
-				{
-					return _enabled;
-				}
-
-				set
-				{
-					_enabled = value;
-					DebuggableCore.MemoryCallbacks.Remove(TraceFromCallback);
-
-					if (_enabled)
-					{
-						DebuggableCore.MemoryCallbacks.Add(new TracingMemoryCallback(TraceFromCallback));
-					}
-				}
-			}
-
-			public string Header { get; set; }
-
-			public IEnumerable<TraceInfo> Contents
-			{
-				get { return Buffer; }
-			}
-
-			public IEnumerable<TraceInfo> TakeContents()
-			{
-				var contents = Buffer.ToList();
-				Buffer.Clear();
-				return contents;
-			}
-
-			public void Put(TraceInfo content)
-			{
-				if (Enabled)
-				{
-					Buffer.Add(content);
-				}
-			}
-
-			public class TracingMemoryCallback : IMemoryCallback
-			{
-				public TracingMemoryCallback(Action callback)
-				{
-					Callback = callback;
-				}
-
-				public MemoryCallbackType Type
-				{
-					get { return MemoryCallbackType.Execute; }
-				}
-
-				public string Name
-				{
-					get { return "Trace Logging"; }
-				}
-
-				public Action Callback { get; private set; }
-
-				public uint? Address
-				{
-					get { return null; }
-				}
-			}
 		}
 	}
 }
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs
index 7cc3449241..2f0040b36d 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs
@@ -162,7 +162,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 				InitMemCallbacks();
 				KillMemCallbacks();
 
-				Tracer = new CallbackBasedTraceBuffer(this);
+				Tracer = new GPGXTraceBuffer(this, MemoryDomains, this);
 				(ServiceProvider as BasicServiceProvider).Register<ITraceable>(Tracer);
 			}
 			catch