diff --git a/Machines/Commodore/Vic-20/Vic20.cpp b/Machines/Commodore/Vic-20/Vic20.cpp
index af4f4db76..a4d8e7523 100644
--- a/Machines/Commodore/Vic-20/Vic20.cpp
+++ b/Machines/Commodore/Vic-20/Vic20.cpp
@@ -28,7 +28,7 @@ Machine::Machine() :
 	// wire up 6522s and serial port
 	_userPortVIA->set_serial_port(_serialPort);
 	_keyboardVIA->set_serial_port(_serialPort);
-	_serialPort->set_vias(_userPortVIA, _keyboardVIA);
+	_serialPort->set_user_port_via(_userPortVIA);
 
 	// wire up the 6522s, tape and machine
 	_userPortVIA->set_delegate(this);
@@ -323,10 +323,3 @@ void Tape::process_input_pulse(Storage::Tape::Pulse pulse)
 		if(_delegate) _delegate->tape_did_change_input(this);
 	}
 }
-
-#pragma mark - Serial Port
-
-void SerialPort::set_input(::Commodore::Serial::Line line, bool value)
-{
-	printf("Serial port line %d: %s\n", line, value ? "on" : "off");
-}
diff --git a/Machines/Commodore/Vic-20/Vic20.hpp b/Machines/Commodore/Vic-20/Vic20.hpp
index ea91d4516..1791b4034 100644
--- a/Machines/Commodore/Vic-20/Vic20.hpp
+++ b/Machines/Commodore/Vic-20/Vic20.hpp
@@ -61,20 +61,6 @@ enum JoystickInput {
 class UserPortVIA;
 class KeyboardVIA;
 
-class SerialPort : public ::Commodore::Serial::Port {
-	public:
-		void set_input(::Commodore::Serial::Line line, bool value);
-
-		void set_vias(std::shared_ptr<UserPortVIA> userPortVIA, std::shared_ptr<KeyboardVIA> keyboardVIA) {
-			_userPortVIA = userPortVIA;
-			_keyboardVIA = keyboardVIA;
-		}
-
-	private:
-		std::weak_ptr<UserPortVIA> _userPortVIA;
-		std::weak_ptr<KeyboardVIA> _keyboardVIA;
-};
-
 class UserPortVIA: public MOS::MOS6522<UserPortVIA>, public MOS::MOS6522IRQDelegate {
 	public:
 		uint8_t get_port_input(Port port) {
@@ -90,6 +76,15 @@ class UserPortVIA: public MOS::MOS6522<UserPortVIA>, public MOS::MOS6522IRQDeleg
 //			}
 		}
 
+		void set_serial_line_state(::Commodore::Serial::Line line, bool value) {
+			printf("Serial port line %d: %s\n", line, value ? "on" : "off");
+			switch(line) {
+				default: break;
+				case ::Commodore::Serial::Line::Data: _portA = (_portA & ~0x02) | (value ? 0 : 0x02);	break;
+				case ::Commodore::Serial::Line::Clock: _portA = (_portA & ~0x01) | (value ? 0 : 0x01);	break;
+			}
+		}
+
 		void set_joystick_state(JoystickInput input, bool value) {
 			if(input != JoystickInput::Right)
 			{
@@ -99,7 +94,7 @@ class UserPortVIA: public MOS::MOS6522<UserPortVIA>, public MOS::MOS6522IRQDeleg
 
 		void set_port_output(Port port, uint8_t value, uint8_t mask) {
 			if(!port) {
-				std::shared_ptr<SerialPort> serialPort = _serialPort.lock();
+				std::shared_ptr<::Commodore::Serial::Port> serialPort = _serialPort.lock();
 				if(serialPort) serialPort->set_output(::Commodore::Serial::Line::Attention, !(value&0x80));
 			}
 		}
@@ -108,13 +103,13 @@ class UserPortVIA: public MOS::MOS6522<UserPortVIA>, public MOS::MOS6522IRQDeleg
 
 		UserPortVIA() : _portA(0xbf) {}
 
-		void set_serial_port(std::shared_ptr<SerialPort> serialPort) {
+		void set_serial_port(std::shared_ptr<::Commodore::Serial::Port> serialPort) {
 			_serialPort = serialPort;
 		}
 
 	private:
 		uint8_t _portA;
-		std::weak_ptr<SerialPort> _serialPort;
+		std::weak_ptr<::Commodore::Serial::Port> _serialPort;
 };
 
 class KeyboardVIA: public MOS::MOS6522<KeyboardVIA>, public MOS::MOS6522IRQDelegate {
@@ -156,7 +151,7 @@ class KeyboardVIA: public MOS::MOS6522<KeyboardVIA>, public MOS::MOS6522IRQDeleg
 
 		void set_control_line_output(Port port, Line line, bool value) {
 			if(line == Line::Two) {
-				std::shared_ptr<SerialPort> serialPort = _serialPort.lock();
+				std::shared_ptr<::Commodore::Serial::Port> serialPort = _serialPort.lock();
 				if(serialPort) {
 					if(port == Port::A) {
 						serialPort->set_output(::Commodore::Serial::Line::Clock, value);
@@ -176,7 +171,7 @@ class KeyboardVIA: public MOS::MOS6522<KeyboardVIA>, public MOS::MOS6522IRQDeleg
 
 		using MOS6522IRQDelegate::set_interrupt_status;
 
-		void set_serial_port(std::shared_ptr<SerialPort> serialPort) {
+		void set_serial_port(std::shared_ptr<::Commodore::Serial::Port> serialPort) {
 			_serialPort = serialPort;
 		}
 
@@ -184,7 +179,22 @@ class KeyboardVIA: public MOS::MOS6522<KeyboardVIA>, public MOS::MOS6522IRQDeleg
 		uint8_t _portB;
 		uint8_t _columns[8];
 		uint8_t _activation_mask;
-		std::weak_ptr<SerialPort> _serialPort;
+		std::weak_ptr<::Commodore::Serial::Port> _serialPort;
+};
+
+class SerialPort : public ::Commodore::Serial::Port {
+	public:
+		void set_input(::Commodore::Serial::Line line, bool value) {
+			std::shared_ptr<UserPortVIA> userPortVIA = _userPortVIA.lock();
+			if(userPortVIA) userPortVIA->set_serial_line_state(line, value);
+		}
+
+		void set_user_port_via(std::shared_ptr<UserPortVIA> userPortVIA) {
+			_userPortVIA = userPortVIA;
+		}
+
+	private:
+		std::weak_ptr<UserPortVIA> _userPortVIA;
 };
 
 class Tape: public Storage::TapePlayer {