diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/LibMelonDS.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/LibMelonDS.cs
index 1c25c14bbf..eefc9ef8f4 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/LibMelonDS.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/LibMelonDS.cs
@@ -101,6 +101,15 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 		[BizImport(CC)]
 		public abstract void SetReg(int ncpu, int index, int val);
 
+		[BizImport(CC)]
+		public abstract int GetCallbackCycleOffset();
+
+		[UnmanagedFunctionPointer(CC)]
+		public delegate void MemoryCallback(uint addr);
+
+		[BizImport(CC)]
+		public abstract void SetMemoryCallback(int which, MemoryCallback callback);
+
 		// bit 0 -> ARM9 or ARM7
 		// bit 1 -> ARM or THUMB mode
 		public enum CpuTypes : uint
@@ -112,7 +121,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 		}
 
 		[UnmanagedFunctionPointer(CC)]
-		public delegate void TraceCallback(CpuTypes _cpu, IntPtr _regs, uint _opcode, long _ccoffset);
+		public delegate void TraceCallback(CpuTypes _cpu, IntPtr _regs, uint _opcode);
 
 		[BizImport(CC)]
 		public abstract void SetTraceCallback(TraceCallback callback);
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.IDebuggable.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.IDebuggable.cs
index 6b3704670f..183fa02e9e 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.IDebuggable.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.IDebuggable.cs
@@ -7,11 +7,6 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 {
 	partial class NDS : IDebuggable
 	{
-		[FeatureNotImplemented]
-		public IMemoryCallbackSystem MemoryCallbacks => throw new NotImplementedException(); // https://github.com/TASEmulators/BizHawk/issues/2585
-
-		public long TotalExecutedCycles => CycleCount;
-
 		public IDictionary<string, RegisterValue> GetCpuFlagsAndRegisters()
 		{
 			uint[] regs = new uint[2 * 16];
@@ -52,5 +47,43 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 
 		[FeatureNotImplemented]
 		public void Step(StepType type) => throw new NotImplementedException();
+
+		public long TotalExecutedCycles => CycleCount + _core.GetCallbackCycleOffset();
+
+		public IMemoryCallbackSystem MemoryCallbacks => _memorycallbacks;
+
+		private readonly MemoryCallbackSystem _memorycallbacks = new(new[] { "System Bus" });
+
+		private LibMelonDS.MemoryCallback _readcb;
+		private LibMelonDS.MemoryCallback _writecb;
+		private LibMelonDS.MemoryCallback _execcb;
+
+		private void InitMemoryCallbacks()
+		{
+			LibMelonDS.MemoryCallback CreateCallback(MemoryCallbackFlags flags, Func<bool> getHasCBOfType)
+			{
+				var rawFlags = (uint)flags;
+				return (address) =>
+				{
+					if (getHasCBOfType())
+					{
+						MemoryCallbacks.CallMemoryCallbacks(address, 0, rawFlags, "System Bus");
+					}
+				};
+			}
+
+			_readcb = CreateCallback(MemoryCallbackFlags.AccessRead, () => MemoryCallbacks.HasReads);
+			_writecb = CreateCallback(MemoryCallbackFlags.AccessWrite, () => MemoryCallbacks.HasWrites);
+			_execcb = CreateCallback(MemoryCallbackFlags.AccessExecute, () => MemoryCallbacks.HasExecutes);
+
+			_memorycallbacks.ActiveChanged += SetMemoryCallbacks;
+		}
+
+		private void SetMemoryCallbacks()
+		{
+			_core.SetMemoryCallback(0, MemoryCallbacks.HasReads ? _readcb : null);
+			_core.SetMemoryCallback(1, MemoryCallbacks.HasWrites ? _writecb : null);
+			_core.SetMemoryCallback(2, MemoryCallbacks.HasExecutes ? _execcb : null);
+		}
 	}
 }
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.ITraceable.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.ITraceable.cs
index ac3ece2f3a..fd3dcd6507 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.ITraceable.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.ITraceable.cs
@@ -10,7 +10,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 		private ITraceable Tracer { get; }
 		private readonly LibMelonDS.TraceCallback _tracecb;
 
-		private void MakeTrace(LibMelonDS.CpuTypes _cpu, IntPtr _regs, uint _opcode, long _ccoffset)
+		private void MakeTrace(LibMelonDS.CpuTypes _cpu, IntPtr _regs, uint _opcode)
 		{
 			string cpu = _cpu switch
 			{
@@ -47,7 +47,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 					(uint)regs[13],
 					(uint)regs[14],
 					(uint)regs[15],
-					CycleCount + _ccoffset,
+					TotalExecutedCycles,
 					cpu)));
 		}
 	}
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.cs
index d03b688e9c..cccc9c36e3 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS.cs
@@ -50,6 +50,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 			bool gbacartpresent = roms.Count > 1;
 			bool gbasrampresent = roms.Count == 3;
 
+			InitMemoryCallbacks();
 			_tracecb = MakeTrace;
 
 			_core = PreInit<LibMelonDS>(new WaterboxOptions
@@ -62,7 +63,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 				MmapHeapSizeKB = 1024 * 1024,
 				SkipCoreConsistencyCheck = CoreComm.CorePreferences.HasFlag(CoreComm.CorePreferencesFlags.WaterboxCoreConsistencyCheck),
 				SkipMemoryConsistencyCheck = CoreComm.CorePreferences.HasFlag(CoreComm.CorePreferencesFlags.WaterboxMemoryConsistencyCheck),
-			}, new Delegate[] { _tracecb });
+			}, new Delegate[] { _readcb, _writecb, _execcb, _tracecb });
 
 			var bios7 = IsDSi || _syncSettings.UseRealBIOS
 				? CoreComm.CoreFileProvider.GetFirmwareOrThrow(new("NDS", "bios7"))