diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Atari2600.cs b/BizHawk.Emulation/Consoles/Atari/2600/Atari2600.cs
index 862699e97d..0f1987ea69 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Atari2600.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Atari2600.cs
@@ -21,6 +21,9 @@ namespace BizHawk
 			CoreComm = comm;
 			var domains = new List<MemoryDomain>(1);
 			domains.Add(new MemoryDomain("Main RAM", 128, Endian.Little, addr => ram[addr & 127], (addr, value) => ram[addr & 127] = value));
+			domains.Add(new MemoryDomain("TIA", 16, Endian.Little, addr => tia.ReadMemory((ushort)addr, true), (addr, value) => tia.WriteMemory((ushort)addr, value)));
+			domains.Add(new MemoryDomain("PIA", 1024, Endian.Little, addr => m6532.ReadMemory((ushort)addr, true), (addr, value) => m6532.WriteMemory((ushort)addr, value)));
+			domains.Add(new MemoryDomain("System Bus", 8192, Endian.Little, addr => mapper.PeekMemory((ushort)addr), (addr, value) => {}));
 			memoryDomains = domains.AsReadOnly();
 			CoreComm.CpuTraceAvailable = true;
 			this.rom = rom;
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m2K.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m2K.cs
index 1ab0901aff..607baa68cf 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m2K.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m2K.cs
@@ -15,6 +15,11 @@ namespace BizHawk
 				if (addr < 0x1000) return base.ReadMemory(addr);
 				return core.rom[addr & 0x7FF];
 			}
+
+			public override byte PeekMemory(ushort addr)
+			{
+				return ReadMemory(addr);
+			}
 		}
 	}
 }
\ No newline at end of file
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3E.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3E.cs
index 52f9e52888..e918651fff 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3E.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3E.cs
@@ -78,6 +78,39 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 			return base.ReadMemory(addr);
 		}
 
+		public override byte PeekMemory(ushort addr)
+		{
+			if (addr < 0x1000)
+			{
+				return base.ReadMemory(addr);
+			}
+			else if (addr < 0x17FF) //Low 2k Bank
+			{
+				if (hasRam)
+				{
+					if (addr < 0x13FF)
+					{
+						return ram[(addr & 0x03FF) + (rambank_1k << 10)];
+					}
+					else
+					{
+						return ram[(addr & 0x03FF) + (rambank_1k << 10)]; //Reading from the write port triggers an unwanted write
+					}
+				}
+				else
+				{
+					int a = addr & 0x07FF; //2K
+					int bank = lowbank_2k << 11;
+					return core.rom[bank + a];
+				}
+			}
+			else if (addr < 0x2000) //High bank fixed to last 2k of ROM
+			{
+				return core.rom[(core.rom.Length - 2048) + (addr & 0x07FF)];
+			}
+			return base.ReadMemory(addr);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			if (addr < 0x1000)
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3F.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3F.cs
index c39d89ecbd..c9f8f2d7e3 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3F.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m3F.cs
@@ -53,6 +53,11 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 			return base.ReadMemory(addr);
 		}
 
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMemory(addr);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			if (addr < 0x0040)
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4A50.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4A50.cs
index ef9cb7aac2..9103f74536 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4A50.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4A50.cs
@@ -45,6 +45,11 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 
 		private ByteBuffer myRAM = new ByteBuffer(32768);
 
+		public override byte PeekMemory(ushort addr)
+		{
+			return base.PeekMemory(addr); //TODO
+		}
+
 		public override byte ReadMemory(ushort addr)
 		{
 			byte val = 0;
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4K.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4K.cs
index aa604e90de..5724be4e12 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4K.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/m4K.cs
@@ -15,6 +15,11 @@ namespace BizHawk
 				if (addr < 0x1000) return base.ReadMemory(addr);
 				return core.rom[addr & 0xFFF];
 			}
+
+			public override byte PeekMemory(ushort addr)
+			{
+				return ReadMemory(addr);
+			}
 		}
 	}
 }
\ No newline at end of file
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mCV.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mCV.cs
index b2eacae9dc..1b36964f2f 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mCV.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mCV.cs
@@ -33,6 +33,12 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 				return core.rom[(addr & 0x7FF)];
 			else return base.ReadMemory(addr);
 		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMemory(addr);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			if (addr < 0x1000)
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mDPC.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mDPC.cs
index 584429e9b6..22ea62f324 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mDPC.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mDPC.cs
@@ -20,6 +20,11 @@ namespace BizHawk
 
 			bool[] MusicMode = new bool[3]; //TOOD: savestates
 
+			public override byte PeekMemory(ushort addr)
+			{
+				return base.PeekMemory(addr); //TODO
+			}
+
 			public override byte ReadMemory(ushort addr)
 			{
 				if (addr < 0x1000)
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE0.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE0.cs
index 554d72aa29..d131860c64 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE0.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE0.cs
@@ -31,17 +31,32 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 		int toggle1 = 0;
 		int toggle2 = 0;
 		int toggle3 = 0;
-		
-		public override byte ReadMemory(ushort addr)
+
+		private byte ReadMem(ushort addr, bool peek)
 		{
-			Address(addr);
+			if (!peek)
+			{
+				Address(addr);
+			}
+
 			if (addr < 0x1000) return base.ReadMemory(addr);
 			else if (addr < 0x1400) return core.rom[toggle1 * 1024 + (addr & 0x3FF)];
 			else if (addr < 0x1800) return core.rom[toggle2 * 1024 + (addr & 0x3FF)];
 			else if (addr < 0x1C00) return core.rom[toggle3 * 1024 + (addr & 0x3FF)];
-			else 
+			else
 				return core.rom[7 * 1024 + (addr & 0x3FF)]; //7 because final bank is always set to last
 		}
+
+		public override byte ReadMemory(ushort addr)
+		{
+			return ReadMem(addr, false);
+		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE7.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE7.cs
index db74fc619e..eaafe98a9b 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE7.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mE7.cs
@@ -38,14 +38,18 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 		ByteBuffer rambank1 = new ByteBuffer(1024);
 		bool EnableRam0 = false;
 
-		public override byte ReadMemory(ushort addr)
+		private byte ReadMem(ushort addr, bool peek)
 		{
 			if (addr < 0x1000)
 			{
 				return base.ReadMemory(addr);
 			}
 
-			Address(addr);
+			if (!peek)
+			{
+				Address(addr);
+			}
+
 			if (addr < 0x1800)
 			{
 				if (EnableRam0)
@@ -84,6 +88,17 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 				return base.ReadMemory(addr);
 			}
 		}
+
+		public override byte ReadMemory(ushort addr)
+		{
+			return ReadMem(addr, false);
+		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mEF.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mEF.cs
index 6c27803a02..62831a4531 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mEF.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mEF.cs
@@ -19,12 +19,27 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 	{
 		int toggle = 0;
 
-		public override byte ReadMemory(ushort addr)
+		private byte ReadMem(ushort addr, bool peek)
 		{
-			Address(addr);
+			if (!peek)
+			{
+				Address(addr);
+			}
+
 			if (addr < 0x1000) return base.ReadMemory(addr);
 			return core.rom[toggle * 4 * 1024 + (addr & 0xFFF)];
 		}
+
+		public override byte ReadMemory(ushort addr)
+		{
+			return ReadMem(addr, false);
+		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF0.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF0.cs
index a774293814..f7616497dd 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF0.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF0.cs
@@ -25,14 +25,28 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 	{
 		int bank = 0;
 
+		private byte ReadMem(ushort addr, bool peek)
+		{
+			if (!peek)
+			{
+				if (addr == 0x1FF0)
+					Increment();
+			}
+
+			if (addr < 0x1000) return base.ReadMemory(addr);
+			else return core.rom[bank * 4096 + (addr & 0xFFF)];
+		}
+
 		public override byte ReadMemory(ushort addr)
 		{
-			if (addr == 0x1FF0)
-				Increment();
-			
-			if (addr < 0x1000) return base.ReadMemory(addr);
-			else return core.rom[bank * 4 * 1024 + (addr & 0xFFF)];
+			return ReadMem(addr, false);
 		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+		
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			if (addr < 0x1000) base.WriteMemory(addr, value);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF4.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF4.cs
index f99ccd30cc..2a76e5cb9a 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF4.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF4.cs
@@ -17,12 +17,27 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 	{
 		int toggle = 0;
 
+		private byte ReadMem(ushort addr, bool peek)
+		{
+			if (!peek)
+			{
+				Address(addr);
+			}
+
+			if (addr < 0x1000) return base.ReadMemory(addr);
+			return core.rom[toggle * 4096 + (addr & 0xFFF)];
+		}
+
 		public override byte ReadMemory(ushort addr)
 		{
-			Address(addr);
-			if (addr < 0x1000) return base.ReadMemory(addr);
-			return core.rom[toggle * 4 * 1024 + (addr & 0xFFF)];
+			return ReadMem(addr, false);
 		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF6.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF6.cs
index 57431f13cb..867df16026 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF6.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF6.cs
@@ -18,12 +18,27 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 	{
 		int toggle = 0;
 
+		private byte ReadMem(ushort addr, bool peek)
+		{
+			if (!peek)
+			{
+				Address(addr);
+			}
+
+			if (addr < 0x1000) return base.ReadMemory(addr);
+			return core.rom[(toggle << 12) + (addr & 0xFFF)];
+		}
+
 		public override byte ReadMemory(ushort addr)
 		{
-			Address(addr);
-			if (addr < 0x1000) return base.ReadMemory(addr);
-			return core.rom[toggle * 4 * 1024 + (addr & 0xFFF)];
+			return ReadMem(addr, false);
 		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF8.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF8.cs
index fe077caf4f..a0f7534fb6 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF8.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mF8.cs
@@ -28,14 +28,28 @@ namespace BizHawk
 		class mF8 : MapperBase
 		{
 			int bank_4k = 0;
-			
+
+			private byte ReadMem(ushort addr, bool peek)
+			{
+				if (!peek)
+				{
+					Address(addr);
+				}
+
+				if (addr < 0x1000) return base.ReadMemory(addr);
+				return core.rom[(bank_4k << 12) + (addr & 0xFFF)];
+			}
 
 			public override byte ReadMemory(ushort addr)
 			{
-				Address(addr);
-				if (addr < 0x1000) return base.ReadMemory(addr);
-				return core.rom[(bank_4k << 12) + (addr&0xFFF)];
+				return ReadMem(addr, false);
 			}
+
+			public override byte PeekMemory(ushort addr)
+			{
+				return ReadMem(addr, true);
+			}
+
 			public override void WriteMemory(ushort addr, byte value)
 			{
 				Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mFA.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mFA.cs
index e5bfa8712b..091e0a737e 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mFA.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mFA.cs
@@ -22,19 +22,41 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 		int toggle = 0;
 		ByteBuffer aux_ram = new ByteBuffer(256);
 
+		private byte ReadMem(ushort addr, bool peek)
+		{
+			if (!peek)
+			{
+				Address(addr);
+			}
+
+			if (addr < 0x1000)
+			{
+				return base.ReadMemory(addr);
+			}
+			else if (addr < 0x1100)
+			{
+				return 0xFF;
+			}
+			else if (addr < 0x1200)
+			{
+				return aux_ram[addr & 0xFF];
+			}
+			else
+			{
+				return core.rom[(toggle * 4096) + (addr & 0xFFF)];
+			}
+		}
+
 		public override byte ReadMemory(ushort addr)
 		{
-			Address(addr);
-
-			if (addr < 0x1000) 
-				return base.ReadMemory(addr);
-			else if (addr < 0x1100)
- 				return 0xFF;
-			else if (addr < 0x1200)
-				return aux_ram[addr & 0xFF];
-			else
-				return core.rom[(toggle * 4 * 1024) + (addr & 0xFFF)];
+			return ReadMem(addr, false);
 		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mUA.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mUA.cs
index d479b80f85..222c172a78 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mUA.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mUA.cs
@@ -19,12 +19,27 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 	{
 		int toggle = 0;
 
+		private byte ReadMem(ushort addr, bool peek)
+		{
+			if (!peek)
+			{
+				Address(addr);
+			}
+			
+			if (addr < 0x1000) return base.ReadMemory(addr);
+			return core.rom[toggle * 4096 + (addr & 0xFFF)];
+		}
+
 		public override byte ReadMemory(ushort addr)
 		{
-			Address(addr);
-			if (addr < 0x1000) return base.ReadMemory(addr);
-			return core.rom[toggle * 4 * 1024 + (addr & 0xFFF)];
+			return ReadMem(addr, false);
 		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs
index 5ca578d2fe..818128129b 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs
@@ -40,9 +40,13 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 	{
 		int rombank_2k = 0;
 
-		public override byte ReadMemory(ushort addr)
+		private byte ReadMem(ushort addr, bool peek)
 		{
-			Address(addr);
+			if (!peek)
+			{
+				Address(addr);
+			}
+
 			if (addr < 0x1000)
 			{
 				return base.ReadMemory(addr);
@@ -52,6 +56,17 @@ namespace BizHawk.Emulation.Consoles.Atari._2600
 				return core.rom[(rombank_2k << 12) + (addr & 0xFFF)];
 			}
 		}
+
+		public override byte ReadMemory(ushort addr)
+		{
+			return ReadMem(addr, false);
+		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMem(addr, true);
+		}
+
 		public override void WriteMemory(ushort addr, byte value)
 		{
 			Address(addr);
diff --git a/BizHawk.MultiClient/MainForm.cs b/BizHawk.MultiClient/MainForm.cs
index c05f24d2c3..5e2070c97f 100644
--- a/BizHawk.MultiClient/MainForm.cs
+++ b/BizHawk.MultiClient/MainForm.cs
@@ -3030,8 +3030,6 @@ namespace BizHawk.MultiClient
 				Global.Sound.UpdateSilence();
 		}
 
-
-
 		/// <summary>
 		/// Update all tools that are frame dependent like Ram Search before processing
 		/// </summary>