diff --git a/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj b/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj
index 7db34731a..9206cb43a 100644
--- a/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj	
+++ b/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj	
@@ -616,6 +616,7 @@
 		4BBFBB6C1EE8401E00C01E7A /* ZX8081.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BBFBB6A1EE8401E00C01E7A /* ZX8081.cpp */; };
 		4BBFE83D21015D9C00BF1C40 /* CSJoystickManager.m in Sources */ = {isa = PBXBuildFile; fileRef = 4BBFE83C21015D9C00BF1C40 /* CSJoystickManager.m */; };
 		4BBFFEE61F7B27F1005F3FEB /* TrackSerialiser.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BBFFEE51F7B27F1005F3FEB /* TrackSerialiser.cpp */; };
+		4BC5C3E022C994CD00795658 /* 68000MoveTests.mm in Sources */ = {isa = PBXBuildFile; fileRef = 4BC5C3DF22C994CC00795658 /* 68000MoveTests.mm */; };
 		4BC5FC3020CDDDEF00410AA0 /* AppleIIOptions.xib in Resources */ = {isa = PBXBuildFile; fileRef = 4BC5FC2E20CDDDEE00410AA0 /* AppleIIOptions.xib */; };
 		4BC751B21D157E61006C31D9 /* 6522Tests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4BC751B11D157E61006C31D9 /* 6522Tests.swift */; };
 		4BC76E691C98E31700E6EF73 /* FIRFilter.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BC76E671C98E31700E6EF73 /* FIRFilter.cpp */; };
@@ -1400,6 +1401,7 @@
 		4BBFE83C21015D9C00BF1C40 /* CSJoystickManager.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = CSJoystickManager.m; sourceTree = "<group>"; };
 		4BBFE83E21015DAE00BF1C40 /* CSJoystickManager.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = CSJoystickManager.h; sourceTree = "<group>"; };
 		4BBFFEE51F7B27F1005F3FEB /* TrackSerialiser.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = TrackSerialiser.cpp; sourceTree = "<group>"; };
+		4BC5C3DF22C994CC00795658 /* 68000MoveTests.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = 68000MoveTests.mm; sourceTree = "<group>"; };
 		4BC5FC2F20CDDDEE00410AA0 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.xib; name = Base; path = "Clock Signal/Base.lproj/AppleIIOptions.xib"; sourceTree = SOURCE_ROOT; };
 		4BC751B11D157E61006C31D9 /* 6522Tests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = 6522Tests.swift; sourceTree = "<group>"; };
 		4BC76E671C98E31700E6EF73 /* FIRFilter.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = FIRFilter.cpp; sourceTree = "<group>"; };
@@ -2938,6 +2940,7 @@
 				4B9D0C4A22C7D70900DE1AD3 /* 68000BCDTests.mm */,
 				4B90467322C6FADD000E2074 /* 68000BitwiseTests.mm */,
 				4B9D0C4C22C7DA1A00DE1AD3 /* 68000ControlFlowTests.mm */,
+				4BC5C3DF22C994CC00795658 /* 68000MoveTests.mm */,
 				4B9D0C4E22C7E0CF00DE1AD3 /* 68000RollShiftTests.mm */,
 				4BD388872239E198002D14B5 /* 68000Tests.mm */,
 				4B924E981E74D22700B76AF1 /* AtariStaticAnalyserTests.mm */,
@@ -4195,6 +4198,7 @@
 				4B90467622C6FD6E000E2074 /* 68000ArithmeticTests.mm in Sources */,
 				4B7BC7F61F58F7D200D1B1B4 /* 6502Base.cpp in Sources */,
 				4B7BC7F51F58F27800D1B1B4 /* 6502AllRAM.cpp in Sources */,
+				4BC5C3E022C994CD00795658 /* 68000MoveTests.mm in Sources */,
 				4B08A2751EE35D56008B7065 /* Z80InterruptTests.swift in Sources */,
 				4BFCA1241ECBDCB400AC40C1 /* AllRAMProcessor.cpp in Sources */,
 				4BBF49AF1ED2880200AB3669 /* FUSETests.swift in Sources */,
diff --git a/OSBindings/Mac/Clock Signal.xcodeproj/xcshareddata/xcschemes/Clock Signal.xcscheme b/OSBindings/Mac/Clock Signal.xcodeproj/xcshareddata/xcschemes/Clock Signal.xcscheme
index 9c2dca9ce..cdac581d4 100644
--- a/OSBindings/Mac/Clock Signal.xcodeproj/xcshareddata/xcschemes/Clock Signal.xcscheme	
+++ b/OSBindings/Mac/Clock Signal.xcodeproj/xcshareddata/xcschemes/Clock Signal.xcscheme	
@@ -69,7 +69,7 @@
       </AdditionalOptions>
    </TestAction>
    <LaunchAction
-      buildConfiguration = "Debug"
+      buildConfiguration = "Release"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       enableASanStackUseAfterReturn = "YES"
diff --git a/OSBindings/Mac/Clock SignalTests/68000ArithmeticTests.mm b/OSBindings/Mac/Clock SignalTests/68000ArithmeticTests.mm
index 5c223e5e1..cde5f63ed 100644
--- a/OSBindings/Mac/Clock SignalTests/68000ArithmeticTests.mm	
+++ b/OSBindings/Mac/Clock SignalTests/68000ArithmeticTests.mm	
@@ -877,6 +877,66 @@
 
 // Omitted: divide by zero test.
 
+// MARK: EXT
+
+- (void)performEXTwd3:(uint32_t)d3 {
+	_machine->set_program({
+		0x4883		// EXT.W D3
+	});
+
+	auto state = _machine->get_processor_state();
+	state.data[3] = d3;
+	state.status = 0x13;
+
+	_machine->set_processor_state(state);
+	_machine->run_for_instructions(1);
+
+	XCTAssertEqual(4, _machine->get_cycle_count());
+}
+
+- (void)testEXTw_78 {
+	[self performEXTwd3:0x12345678];
+
+	const auto state = _machine->get_processor_state();
+	XCTAssertEqual(state.data[3], 0x12340078);
+	XCTAssertEqual(state.status & Flag::ConditionCodes, Flag::Extend);
+}
+
+- (void)testEXTw_00 {
+	[self performEXTwd3:0x12345600];
+
+	const auto state = _machine->get_processor_state();
+	XCTAssertEqual(state.data[3], 0x12340000);
+	XCTAssertEqual(state.status & Flag::ConditionCodes, Flag::Extend | Flag::Zero);
+}
+
+- (void)testEXTw_f0 {
+	[self performEXTwd3:0x123456f0];
+
+	const auto state = _machine->get_processor_state();
+	XCTAssertEqual(state.data[3], 0x1234fff0);
+	XCTAssertEqual(state.status & Flag::ConditionCodes, Flag::Extend | Flag::Negative);
+}
+
+- (void)testEXTl {
+	_machine->set_program({
+		0x48c3		// EXT.L D3
+	});
+
+	auto state = _machine->get_processor_state();
+	state.data[3] = 0x1234f6f0;
+	state.status = 0x13;
+
+	_machine->set_processor_state(state);
+	_machine->run_for_instructions(1);
+
+	XCTAssertEqual(4, _machine->get_cycle_count());
+
+	state = _machine->get_processor_state();
+	XCTAssertEqual(state.data[3], 0xfffff6f0);
+	XCTAssertEqual(state.status & Flag::ConditionCodes, Flag::Extend | Flag::Negative);
+}
+
 // MARK: MULS
 
 - (void)performMULSd1:(uint32_t)d1 d2:(uint32_t)d2 ccr:(uint8_t)ccr {
diff --git a/OSBindings/Mac/Clock SignalTests/TestRunner68000.hpp b/OSBindings/Mac/Clock SignalTests/TestRunner68000.hpp
index 7fa8a1585..756628be4 100644
--- a/OSBindings/Mac/Clock SignalTests/TestRunner68000.hpp	
+++ b/OSBindings/Mac/Clock SignalTests/TestRunner68000.hpp	
@@ -11,6 +11,7 @@
 
 #include <array>
 
+#define LOG_TRACE
 #include "../../../Processors/68000/68000.hpp"
 
 using Flag = CPU::MC68000::Flag;
@@ -132,7 +133,7 @@ class RAM68000: public CPU::MC68000::BusHandler {
 
 	private:
 		CPU::MC68000::Processor<RAM68000, true, true> m68000_;
-		std::array<uint16_t, 256*1024> ram_;
+		std::array<uint16_t, 256*1024> ram_{};
 		int instructions_remaining_;
 		HalfCycles duration_;
 		bool has_run_ = false;