diff --git a/ReadMe.txt b/ReadMe.txt
index edc212b..b9e8caf 100644
--- a/ReadMe.txt
+++ b/ReadMe.txt
@@ -55,19 +55,19 @@ LINKS
 
 CHANGES
 
-Version 2.3 (2021-02-xx)
+Version 2.3 (2021-09-xx)
 
 - Add the serial port support (via USB OTG).
 	FIX: When stop the app, Serial exception seems to delay the save of the calc state!!!!
 	FIX: Inform if the connection is not possible.
+	FIX: No 'No driver' on real device
+	FIX: ID change -> replace id by vendor:device ids?
 	BUG: From Windows to Android with HP49G QINHENG CH340 -> all character at once bug
 		No issue with Prolific PL2303GT3
 		Not reproducible!
-	FIX: No 'No driver' on real device
 	BUG: When openIO on real device, 1st OPENIO failed, 2nd OPENIO succeeded
-	BUG: ID change -> replace id by vendor:device ids?
 	TEST: With real HP48SX
-	TODO: Check the self test about UART (http://regis.cosnier.free.fr/private/private.php?journal=HP48&index=-4637&nomenu)
+	TODO: Check the self test about UART
 - Allows pressing a calculator button with the right button of the mouse and prevents its release to allow the On+A+F key combination (with Android version >= 5.0).
 - Update the embedded help file "Emu48.html" to the latest version.
 - Open an external web browser when you click an external links in the Help.
diff --git a/app/src/main/assets/ReadMe.txt b/app/src/main/assets/ReadMe.txt
index adb5505..19a3478 100644
--- a/app/src/main/assets/ReadMe.txt
+++ b/app/src/main/assets/ReadMe.txt
@@ -55,14 +55,10 @@ LINKS
 
 CHANGES
 
-Version 2.3 (2021-02-xx)
+Version 2.3 (2021-09-xx)
 
 - Add the serial port support (via USB OTG).
-	TODO: When stop the app, Serial exception seems to delay the save of the calc state!!!!
-	TODO: Inform if the connection is not possible.
-	TODO: What's happen if I hot unplug?
-	TODO: Check the self test about UART (http://regis.cosnier.free.fr/private/private.php?journal=HP48&index=-4637&nomenu)
-- Allows pressing a calculator button with the right button of the mouse but prevents its release to allow the On+A+F key combination (with Android version >= 5.0).
+- Allows pressing a calculator button with the right button of the mouse and prevents its release to allow the On+A+F key combination (with Android version >= 5.0).
 - Update the embedded help file "Emu48.html" to the latest version.
 - Open an external web browser when you click an external links in the Help.
 
diff --git a/app/src/main/cpp/emu-jni.c b/app/src/main/cpp/emu-jni.c
index 862dd2c..be894af 100644
--- a/app/src/main/cpp/emu-jni.c
+++ b/app/src/main/cpp/emu-jni.c
@@ -1297,7 +1297,7 @@ JNIEXPORT void JNICALL Java_org_emulator_calculator_NativeLib_setConfiguration(J
             SwitchToState(nOldState);
         }
     } else if(_tcscmp(_T("settings_serial_ports_wire"), configKey) == 0) {
-	    const char * newSerialWire = _tcscmp(_T("0,0"), configStringValue) == 0 ? NO_SERIAL : configStringValue;
+	    const char * newSerialWire = _tcscmp(_T("0000:0000,0"), configStringValue) == 0 ? NO_SERIAL : configStringValue;
 	    BOOL serialWireChanged = _tcscmp(szSerialWire, newSerialWire) != 0;
 	    _tcsncpy(szSerialWire, newSerialWire, sizeof(szSerialWire));
 	    if(bCommInit && serialWireChanged) {
@@ -1305,7 +1305,7 @@ JNIEXPORT void JNICALL Java_org_emulator_calculator_NativeLib_setConfiguration(J
 		    bCommInit = CommOpen(szSerialWire, szSerialIr);
 	    }
     } else if(_tcscmp(_T("settings_serial_ports_ir"), configKey) == 0) {
-	    const char * newSerialIr = _tcscmp(_T("0,0"), configStringValue) == 0 ? NO_SERIAL : configStringValue;
+	    const char * newSerialIr = _tcscmp(_T("0000:0000,0"), configStringValue) == 0 ? NO_SERIAL : configStringValue;
 	    BOOL serialIrChanged = _tcscmp(szSerialIr, newSerialIr) != 0;
 	    _tcsncpy(szSerialIr, newSerialIr, sizeof(szSerialIr));
 	    if(bCommInit && serialIrChanged) {
diff --git a/app/src/main/java/org/emulator/calculator/Serial.java b/app/src/main/java/org/emulator/calculator/Serial.java
index e7770f8..f18c8f9 100644
--- a/app/src/main/java/org/emulator/calculator/Serial.java
+++ b/app/src/main/java/org/emulator/calculator/Serial.java
@@ -73,24 +73,37 @@ public class Serial {
 	public synchronized boolean connect(String serialPort) {
 		if(debug) Log.d(TAG, "connect( " + serialPort + ")");
 
-		Pattern patternSerialPort = Pattern.compile("\\\\.\\\\(\\d+),(\\d+)");
+		Pattern patternSerialPort = Pattern.compile("\\\\.\\\\([0-9a-fA-F]+):([0-9a-fA-F]+),(\\d+)");
 		Matcher m = patternSerialPort.matcher(serialPort);
 		if (m.find()) {
-			String deviceText = m.group(1);
-			String portText = m.group(2);
-			int deviceId = 0;
-			try {
-				deviceId = Integer.parseInt(deviceText);
-			} catch (NumberFormatException ex) {
-				// Catch bad number format
+			String vendorIdText = m.group(1);
+			String productIdText = m.group(2);
+			String portText = m.group(3);
+			int vendorId = 0;
+			if(vendorIdText != null) {
+				try {
+					vendorId = Integer.parseInt(vendorIdText, 16);
+				} catch (NumberFormatException ex) {
+					// Catch bad number format
+				}
+			}
+			int productId = 0;
+			if(productIdText != null) {
+				try {
+					productId = Integer.parseInt(productIdText, 16);
+				} catch (NumberFormatException ex) {
+					// Catch bad number format
+				}
 			}
 			int portNum = 0;
-			try {
-				portNum = Integer.parseInt(portText);
-			} catch (NumberFormatException ex) {
-				// Catch bad number format
+			if(portText != null) {
+				try {
+					portNum = Integer.parseInt(portText);
+				} catch (NumberFormatException ex) {
+					// Catch bad number format
+				}
 			}
-			return connect(deviceId, portNum);
+			return connect(vendorId, productId, portNum);
 		}
 		return false;
 	}
@@ -99,14 +112,16 @@ public class Serial {
 		return connectionStatus;
 	}
 
-	public synchronized boolean connect(int deviceId, int portNum) {
-		if(debug) Log.d(TAG, "connect(deviceId: " + deviceId + ", portNum" + portNum + ")");
+	public synchronized boolean connect(int vendorId, int productId, int portNum) {
+		if(debug) Log.d(TAG, String.format("connect('%04X:%04X', portNum: %d)", vendorId, productId, portNum));
 
 		UsbDevice device = null;
 		UsbManager usbManager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
 		for(UsbDevice v : usbManager.getDeviceList().values())
-			if(v.getDeviceId() == deviceId)
+			if(v.getVendorId() == vendorId && v.getProductId() == productId) {
 				device = v;
+				break;
+			}
 		if(device == null) {
 			connectionStatus = "serial_connection_failed_device_not_found";
 			if(debug) Log.d(TAG, "connectionStatus = " + connectionStatus);
@@ -127,7 +142,7 @@ public class Serial {
 			return false;
 		}
 		usbSerialPort = driver.getPorts().get(portNum);
-		UsbDeviceConnection usbConnection = null;
+		UsbDeviceConnection usbConnection;
 		try {
 			usbConnection = usbManager.openDevice(driver.getDevice());
 		} catch (SecurityException e) {
diff --git a/app/src/main/java/org/emulator/calculator/usbserial/DevicesFragment.java b/app/src/main/java/org/emulator/calculator/usbserial/DevicesFragment.java
index d9a7ebf..d6a1010 100644
--- a/app/src/main/java/org/emulator/calculator/usbserial/DevicesFragment.java
+++ b/app/src/main/java/org/emulator/calculator/usbserial/DevicesFragment.java
@@ -106,21 +106,18 @@ public class DevicesFragment extends ListFragment {
     }
 
 	public static class SerialConnectParameters {
-		public int deviceId;
 		public int port;
 		public int vendorId;
 		public int productId;
 		public String modelName;
 
 		public SerialConnectParameters() {
-			this.deviceId = 0;
 			this.port = 0;
 			this.vendorId = 0;
 			this.productId = 0;
 			this.modelName = "";
 		}
-		public SerialConnectParameters(int device, int port, int vendorId, int productId, String modelName) {
-			this.deviceId = device;
+		public SerialConnectParameters(int port, int vendorId, int productId, String modelName) {
 			this.port = port;
 			this.vendorId = vendorId;
 			this.productId = productId;
@@ -128,18 +125,18 @@ public class DevicesFragment extends ListFragment {
 		}
 
 		public String toSettingsString() {
-			return String.format(Locale.US, "%d,%d,%d,%d,%s", deviceId, port, vendorId, productId, modelName);
+			return String.format(Locale.US, "%d,%d,%d,%s", port, vendorId, productId, modelName);
 		}
 
 		public String toWin32String() {
-			return String.format(Locale.US, "%d,%d", deviceId, port);
+			return String.format(Locale.US, "%04X:%04X,%d", vendorId, productId, port);
 		}
 
 		public String toDisplayString(Context context) {
-			if(deviceId == 0 && port == 0)
+			if(vendorId == 0 && productId == 0 && port == 0)
 				return context.getResources().getString(Utils.resId(context, "string", "serial_ports_device_no_driver"));
 			else
-				return String.format(Locale.US, context.getResources().getString(Utils.resId(context, "string", "serial_ports_device")), modelName, vendorId, productId, deviceId, port);
+				return String.format(Locale.US, context.getResources().getString(Utils.resId(context, "string", "serial_ports_device")), modelName, vendorId, productId, port);
 		}
 
 		public static SerialConnectParameters fromSettingsString(String serialPorts) {
@@ -149,19 +146,13 @@ public class DevicesFragment extends ListFragment {
 		}
 
 		private void fromSettingsStringExtractor(String serialPorts) {
-			Pattern patternSerialPort = Pattern.compile("(\\d+),(\\d+),(\\d+),(\\d+),([^,]+)");
+			Pattern patternSerialPort = Pattern.compile("(\\d+),(\\d+),(\\d+),([^,]+)");
 			Matcher m = patternSerialPort.matcher(serialPorts);
 			if (m.find()) {
-				String deviceText = m.group(1);
-				String portText = m.group(2);
-				String vendorIdText = m.group(3);
-				String productIdText = m.group(4);
-				modelName = m.group(5);
-				try {
-					deviceId = Integer.parseInt(deviceText);
-				} catch (NumberFormatException ex) {
-					// Catch bad number format
-				}
+				String portText = m.group(1);
+				String vendorIdText = m.group(2);
+				String productIdText = m.group(3);
+				modelName = m.group(4);
 				try {
 					port = Integer.parseInt(portText);
 				} catch (NumberFormatException ex) {
@@ -207,12 +198,12 @@ public class DevicesFragment extends ListFragment {
         if(item.driver == null) {
             Toast.makeText(getActivity(), getString(Utils.resId(this, "string", "serial_ports_device_no_driver")), Toast.LENGTH_SHORT).show();
 	        if(onSerialDeviceClickedListener != null)
-		        onSerialDeviceClickedListener.onSerialDeviceClicked(new SerialConnectParameters(0, 0,
+		        onSerialDeviceClickedListener.onSerialDeviceClicked(new SerialConnectParameters(0,
 				        0, 0,
 				        ""));
         } else if(item.device != null) {
         	if(onSerialDeviceClickedListener != null)
-		        onSerialDeviceClickedListener.onSerialDeviceClicked(new SerialConnectParameters(item.device.getDeviceId(), item.port,
+		        onSerialDeviceClickedListener.onSerialDeviceClicked(new SerialConnectParameters(item.port,
 				        item.device.getVendorId(), item.device.getProductId(),
 				        item.driver.getClass().getSimpleName().replace("SerialDriver","")));
         }
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index bb53dda..0fab206 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -131,7 +131,7 @@
 	<string name="serial_fragment_title">USB Devices</string>
 	<string name="serial_device_list_header">USB Devices</string>
 	<string name="serial_no_device">no USB devices found</string>
-	<string name="serial_ports_device">%s (%04X:%04X) [%d,%d]</string>
+	<string name="serial_ports_device">%s (%04X:%04X) [%d]</string>
 	<string name="serial_ports_device_no_driver">No driver</string>
 	<string name="serial_ports_device_item_title">%s, Port %d</string>
 	<string name="serial_ports_device_item_description">Vendor %04X, Product %04X</string>
@@ -218,8 +218,8 @@
     <string name="settings_macro_real_speed_title">Use Real Replay Speed</string>
     <string name="settings_macro_manual_speed_title">Manual Replay Speed</string>
 
-	<string name="settings_category_serial_ports_title">Serial Ports</string>
+	<string name="settings_category_serial_ports_title">Serial Ports (Please allow USB OTG)</string>
 	<string name="settings_serial_ports_wire_title">Wire</string>
-	<string name="settings_serial_ports_ir_title">Infrared (2400 baud)</string>
+	<string name="settings_serial_ports_ir_title">Infrared (2400 baud only)</string>
 
 </resources>