Check for valid file descriptor before closing and add RS485 mode

src/main/c/Android/jni/SerialPort_Android.c

@@ -2,7 +2,7 @@
  * SerialPort_Android.c
  *
  *       Created on:  Mar 13, 2015
- *  Last Updated on:  Apr 15, 2019
+ *  Last Updated on:  Jul 08, 2019
  *           Author:  Will Hedgecock
  *
  * Copyright (C) 2012-2019 Fazecast, Inc.
@@ -66,6 +66,9 @@ jfieldID parityField;
 jfieldID flowControlField;
 jfieldID sendDeviceQueueSizeField;
 jfieldID receiveDeviceQueueSizeField;
+jfieldID rs485ModeField;
+jfieldID rs485DelayBeforeField;
+jfieldID rs485DelayAfterField;
 jfieldID timeoutModeField;
 jfieldID readTimeoutField;
 jfieldID writeTimeoutField;
@@ -121,6 +124,9 @@ JNIEXPORT void JNICALL Java_com_fazecast_jSerialComm_SerialPort_initializeLibrar
 	flowControlField = (*env)->GetFieldID(env, serialCommClass, "flowControl", "I");
 	sendDeviceQueueSizeField = (*env)->GetFieldID(env, serialCommClass, "sendDeviceQueueSize", "I");
 	receiveDeviceQueueSizeField = (*env)->GetFieldID(env, serialCommClass, "receiveDeviceQueueSize", "I");
+	rs485ModeField = (*env)->GetFieldID(env, serialCommClass, "rs485Mode", "Z");
+	rs485DelayBeforeField = (*env)->GetFieldID(env, serialCommClass, "rs485DelayBefore", "I");
+	rs485DelayAfterField = (*env)->GetFieldID(env, serialCommClass, "rs485DelayAfter", "I");
 	timeoutModeField = (*env)->GetFieldID(env, serialCommClass, "timeoutMode", "I");
 	readTimeoutField = (*env)->GetFieldID(env, serialCommClass, "readTimeout", "I");
 	writeTimeoutField = (*env)->GetFieldID(env, serialCommClass, "writeTimeout", "I");
@@ -193,7 +199,10 @@ JNIEXPORT jboolean JNICALL Java_com_fazecast_jSerialComm_SerialPort_configPort(J
 	int flowControl = (*env)->GetIntField(env, obj, flowControlField);
 	int sendDeviceQueueSize = (*env)->GetIntField(env, obj, sendDeviceQueueSizeField);
 	int receiveDeviceQueueSize = (*env)->GetIntField(env, obj, receiveDeviceQueueSizeField);
+	int rs485DelayBefore = (*env)->GetIntField(env, obj, rs485DelayBeforeField);
+	int rs485DelayAfter = (*env)->GetIntField(env, obj, rs485DelayAfterField);
 	unsigned char configDisabled = (*env)->GetBooleanField(env, obj, disableConfigField);
+	unsigned char rs485ModeEnabled = (*env)->GetBooleanField(env, obj, rs485ModeField);
 	unsigned char isDtrEnabled = (*env)->GetBooleanField(env, obj, isDtrEnabledField);
 	unsigned char isRtsEnabled = (*env)->GetBooleanField(env, obj, isRtsEnabledField);
 	tcflag_t byteSize = (byteSizeInt == 5) ? CS5 : (byteSizeInt == 6) ? CS6 : (byteSizeInt == 7) ? CS7 : CS8;
@@ -255,6 +264,19 @@ JNIEXPORT jboolean JNICALL Java_com_fazecast_jSerialComm_SerialPort_configPort(J
 	ioctl(serialPortFD, TIOCSSERIAL, &serInfo);
 	if (baudRateCode == 0)
 		setBaudRate(serialPortFD, baudRate);
+
+	// Attempt to set the requested RS-485 mode
+	struct serial_rs485 rs485Conf;
+	if (ioctl(serialPortFD, TIOCGRS485, &rs485Conf) == 0)
+	{
+		if (rs485ModeEnabled)
+			rs485Conf.flags |= SER_RS485_ENABLED;
+		else
+			rs485Conf.flags &= ~SER_RS485_ENABLED;
+		rs485Conf.delay_rts_before_send = rs485DelayBefore;
+		rs485Conf.delay_rts_after_send = rs485DelayAfter;
+		ioctl(serialPortFD, TIOCSRS485, &rs485Conf);
+	}
 	return ((retVal == 0) && Java_com_fazecast_jSerialComm_SerialPort_configEventFlags(env, obj, serialPortFD) ? JNI_TRUE : JNI_FALSE);
 }
 
@@ -454,7 +476,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 			if (numBytesRead == -1)
 			{
 				// Problem reading, close port
-				while ((close(serialPortFD) == -1) && (errno != EBADF));
+				while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 				serialPortFD = -1;
 				(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 				(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);
@@ -485,7 +507,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 			if (numBytesRead == -1)
 			{
 				// Problem reading, close port
-				while ((close(serialPortFD) == -1) && (errno != EBADF));
+				while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 				serialPortFD = -1;
 				(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 				(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);
@@ -508,7 +530,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 		if (numBytesRead == -1)
 		{
 			// Problem reading, close port
-			while ((close(serialPortFD) == -1) && (errno != EBADF));
+			while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 			serialPortFD = -1;
 			(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 			(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);
@@ -538,7 +560,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_writeBytes(JNIEn
 		// Problem writing, allow others to open the port and close it ourselves
 		ioctl(serialPortFD, TIOCNXCL);
 		ioctl(serialPortFD, TCSBRK, 1);
-		while ((close(serialPortFD) == -1) && (errno != EBADF));
+		while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 		serialPortFD = -1;
 		(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 		(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);

src/main/c/Posix/SerialPort_Posix.c

@@ -2,7 +2,7 @@
  * SerialPort_Posix.c
  *
  *       Created on:  Feb 25, 2012
- *  Last Updated on:  Apr 15, 2019
+ *  Last Updated on:  Jul 08, 2019
  *           Author:  Will Hedgecock
  *
  * Copyright (C) 2012-2019 Fazecast, Inc.
@@ -64,6 +64,9 @@ jfieldID parityField;
 jfieldID flowControlField;
 jfieldID sendDeviceQueueSizeField;
 jfieldID receiveDeviceQueueSizeField;
+jfieldID rs485ModeField;
+jfieldID rs485DelayBeforeField;
+jfieldID rs485DelayAfterField;
 jfieldID timeoutModeField;
 jfieldID readTimeoutField;
 jfieldID writeTimeoutField;
@@ -225,6 +228,9 @@ JNIEXPORT void JNICALL Java_com_fazecast_jSerialComm_SerialPort_initializeLibrar
 	flowControlField = (*env)->GetFieldID(env, serialCommClass, "flowControl", "I");
 	sendDeviceQueueSizeField = (*env)->GetFieldID(env, serialCommClass, "sendDeviceQueueSize", "I");
 	receiveDeviceQueueSizeField = (*env)->GetFieldID(env, serialCommClass, "receiveDeviceQueueSize", "I");
+	rs485ModeField = (*env)->GetFieldID(env, serialCommClass, "rs485Mode", "Z");
+	rs485DelayBeforeField = (*env)->GetFieldID(env, serialCommClass, "rs485DelayBefore", "I");
+	rs485DelayAfterField = (*env)->GetFieldID(env, serialCommClass, "rs485DelayAfter", "I");
 	timeoutModeField = (*env)->GetFieldID(env, serialCommClass, "timeoutMode", "I");
 	readTimeoutField = (*env)->GetFieldID(env, serialCommClass, "readTimeout", "I");
 	writeTimeoutField = (*env)->GetFieldID(env, serialCommClass, "writeTimeout", "I");
@@ -307,7 +313,10 @@ JNIEXPORT jboolean JNICALL Java_com_fazecast_jSerialComm_SerialPort_configPort(J
 	int flowControl = (*env)->GetIntField(env, obj, flowControlField);
 	int sendDeviceQueueSize = (*env)->GetIntField(env, obj, sendDeviceQueueSizeField);
 	int receiveDeviceQueueSize = (*env)->GetIntField(env, obj, receiveDeviceQueueSizeField);
+	int rs485DelayBefore = (*env)->GetIntField(env, obj, rs485DelayBeforeField);
+	int rs485DelayAfter = (*env)->GetIntField(env, obj, rs485DelayAfterField);
 	unsigned char configDisabled = (*env)->GetBooleanField(env, obj, disableConfigField);
+	unsigned char rs485ModeEnabled = (*env)->GetBooleanField(env, obj, rs485ModeField);
 	unsigned char isDtrEnabled = (*env)->GetBooleanField(env, obj, isDtrEnabledField);
 	unsigned char isRtsEnabled = (*env)->GetBooleanField(env, obj, isRtsEnabledField);
 	tcflag_t byteSize = (byteSizeInt == 5) ? CS5 : (byteSizeInt == 6) ? CS6 : (byteSizeInt == 7) ? CS7 : CS8;
@@ -347,8 +356,7 @@ JNIEXPORT jboolean JNICALL Java_com_fazecast_jSerialComm_SerialPort_configPort(J
 	// Attempt to set the transmit buffer size and any necessary custom baud rates
 #if defined(__linux__)
 	struct serial_struct serInfo;
-	int ioctlRetVal = ioctl(serialPortFD, TIOCGSERIAL, &serInfo);
-	if (ioctlRetVal == 0)
+	if (ioctl(serialPortFD, TIOCGSERIAL, &serInfo) == 0)
 	{
 		serInfo.xmit_fifo_size = sendDeviceQueueSize;
 		ioctl(serialPortFD, TIOCSSERIAL, &serInfo);
@@ -356,6 +364,21 @@ JNIEXPORT jboolean JNICALL Java_com_fazecast_jSerialComm_SerialPort_configPort(J
 #endif
 	if (nonStandardBaudRate)
 		setBaudRateCustom(serialPortFD, baudRate);
+
+	// Attempt to set the requested RS-485 mode
+#if defined(__linux__)
+	struct serial_rs485 rs485Conf;
+	if (ioctl(serialPortFD, TIOCGRS485, &rs485Conf) == 0)
+	{
+		if (rs485ModeEnabled)
+			rs485Conf.flags |= SER_RS485_ENABLED;
+		else
+			rs485Conf.flags &= ~SER_RS485_ENABLED;
+		rs485Conf.delay_rts_before_send = rs485DelayBefore;
+		rs485Conf.delay_rts_after_send = rs485DelayAfter;
+		ioctl(serialPortFD, TIOCSRS485, &rs485Conf);
+	}
+#endif
 	return ((retVal == 0) && Java_com_fazecast_jSerialComm_SerialPort_configEventFlags(env, obj, serialPortFD) ? JNI_TRUE : JNI_FALSE);
 }
 
@@ -538,7 +561,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 				// Problem reading, allow others to open the port and close it ourselves
 				ioctl(serialPortFD, TIOCNXCL);
 				tcdrain(serialPortFD);
-				while ((close(serialPortFD) == -1) && (errno != EBADF));
+				while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 				serialPortFD = -1;
 				(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 				(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);
@@ -571,7 +594,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 				// Problem reading, allow others to open the port and close it ourselves
 				ioctl(serialPortFD, TIOCNXCL);
 				tcdrain(serialPortFD);
-				while ((close(serialPortFD) == -1) && (errno != EBADF));
+				while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 				serialPortFD = -1;
 				(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 				(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);
@@ -596,7 +619,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 			// Problem reading, allow others to open the port and close it ourselves
 			ioctl(serialPortFD, TIOCNXCL);
 			tcdrain(serialPortFD);
-			while ((close(serialPortFD) == -1) && (errno != EBADF));
+			while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 			serialPortFD = -1;
 			(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 			(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);
@@ -631,7 +654,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_writeBytes(JNIEn
 		// Problem writing, allow others to open the port and close it ourselves
 		ioctl(serialPortFD, TIOCNXCL);
 		tcdrain(serialPortFD);
-		while ((close(serialPortFD) == -1) && (errno != EBADF));
+		while (((*env)->GetBooleanField(env, obj, isOpenedField)) && (close(serialPortFD) == -1) && (errno != EBADF));
 		serialPortFD = -1;
 		(*env)->SetLongField(env, obj, serialPortFdField, -1l);
 		(*env)->SetBooleanField(env, obj, isOpenedField, JNI_FALSE);

src/main/c/Windows/SerialPort_Windows.c

@@ -2,7 +2,7 @@
  * SerialPort_Windows.c
  *
  *       Created on:  Feb 25, 2012
- *  Last Updated on:  Mar 07, 2019
+ *  Last Updated on:  Jul 08, 2019
  *           Author:  Will Hedgecock
  *
  * Copyright (C) 2012-2019 Fazecast, Inc.
@@ -57,6 +57,9 @@ jfieldID parityField;
 jfieldID flowControlField;
 jfieldID sendDeviceQueueSizeField;
 jfieldID receiveDeviceQueueSizeField;
+jfieldID rs485ModeField;
+jfieldID rs485DelayBeforeField;
+jfieldID rs485DelayAfterField;
 jfieldID timeoutModeField;
 jfieldID readTimeoutField;
 jfieldID writeTimeoutField;
@@ -358,6 +361,9 @@ JNIEXPORT void JNICALL Java_com_fazecast_jSerialComm_SerialPort_initializeLibrar
 	flowControlField = env->GetFieldID(serialCommClass, "flowControl", "I");
 	sendDeviceQueueSizeField = env->GetFieldID(serialCommClass, "sendDeviceQueueSize", "I");
 	receiveDeviceQueueSizeField = env->GetFieldID(serialCommClass, "receiveDeviceQueueSize", "I");
+	rs485ModeField = env->GetFieldID(serialCommClass, "rs485Mode", "Z");
+	rs485DelayBeforeField = env->GetFieldID(serialCommClass, "rs485DelayBefore", "I");
+	rs485DelayAfterField = env->GetFieldID(serialCommClass, "rs485DelayAfter", "I");
 	timeoutModeField = env->GetFieldID(serialCommClass, "timeoutMode", "I");
 	readTimeoutField = env->GetFieldID(serialCommClass, "readTimeout", "I");
 	writeTimeoutField = env->GetFieldID(serialCommClass, "writeTimeout", "I");
@@ -414,6 +420,7 @@ JNIEXPORT jboolean JNICALL Java_com_fazecast_jSerialComm_SerialPort_configPort(J
 	DWORD sendDeviceQueueSize = (DWORD)env->GetIntField(obj, sendDeviceQueueSizeField);
 	DWORD receiveDeviceQueueSize = (DWORD)env->GetIntField(obj, receiveDeviceQueueSizeField);
 	BYTE configDisabled = (BYTE)env->GetBooleanField(obj, disableConfigField);
+	BYTE rs485ModeEnabled = (BYTE)env->GetBooleanField(obj, rs485ModeField);
 	BYTE isDtrEnabled = env->GetBooleanField(obj, isDtrEnabledField);
 	BYTE isRtsEnabled = env->GetBooleanField(obj, isRtsEnabledField);
 	BYTE stopBits = (stopBitsInt == com_fazecast_jSerialComm_SerialPort_ONE_STOP_BIT) ? ONESTOPBIT : (stopBitsInt == com_fazecast_jSerialComm_SerialPort_ONE_POINT_FIVE_STOP_BITS) ? ONE5STOPBITS : TWOSTOPBITS;
@@ -424,7 +431,8 @@ JNIEXPORT jboolean JNICALL Java_com_fazecast_jSerialComm_SerialPort_configPort(J
 	BOOL DSREnabled = (((flowControl & com_fazecast_jSerialComm_SerialPort_FLOW_CONTROL_DSR_ENABLED) > 0) ||
 			((flowControl & com_fazecast_jSerialComm_SerialPort_FLOW_CONTROL_DTR_ENABLED) > 0));
 	BYTE DTRValue = ((flowControl & com_fazecast_jSerialComm_SerialPort_FLOW_CONTROL_DTR_ENABLED) > 0) ? DTR_CONTROL_HANDSHAKE : (isDtrEnabled ? DTR_CONTROL_ENABLE : DTR_CONTROL_DISABLE);
-	BYTE RTSValue = ((flowControl & com_fazecast_jSerialComm_SerialPort_FLOW_CONTROL_RTS_ENABLED) > 0) ? RTS_CONTROL_HANDSHAKE : (isRtsEnabled ? RTS_CONTROL_ENABLE : RTS_CONTROL_DISABLE);
+	BYTE RTSValue = (rs485ModeEnabled ? RTS_CONTROL_TOGGLE :
+			(((flowControl & com_fazecast_jSerialComm_SerialPort_FLOW_CONTROL_RTS_ENABLED) > 0) ? RTS_CONTROL_HANDSHAKE : (isRtsEnabled ? RTS_CONTROL_ENABLE : RTS_CONTROL_DISABLE)));
 	BOOL XonXoffInEnabled = ((flowControl & com_fazecast_jSerialComm_SerialPort_FLOW_CONTROL_XONXOFF_IN_ENABLED) > 0);
 	BOOL XonXoffOutEnabled = ((flowControl & com_fazecast_jSerialComm_SerialPort_FLOW_CONTROL_XONXOFF_OUT_ENABLED) > 0);
 
@@ -566,7 +574,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_waitForEvent(JNI
 			// Problem reading, close port
 			int numRetries = 10;
 			PurgeComm(serialPortHandle, PURGE_RXABORT | PURGE_RXCLEAR | PURGE_TXABORT | PURGE_TXCLEAR);
-			while (!CloseHandle(serialPortHandle) && (numRetries-- > 0));
+			while (env->GetBooleanField(obj, isOpenedField) && !CloseHandle(serialPortHandle) && (numRetries-- > 0));
 			serialPortHandle = INVALID_HANDLE_VALUE;
 			env->SetLongField(obj, serialPortHandleField, -1l);
 			env->SetBooleanField(obj, isOpenedField, JNI_FALSE);
@@ -674,7 +682,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 			// Problem reading, close port
 			int numRetries = 10;
 			PurgeComm(serialPortHandle, PURGE_RXABORT | PURGE_RXCLEAR | PURGE_TXABORT | PURGE_TXCLEAR);
-			while (!CloseHandle(serialPortHandle) && (numRetries-- > 0));
+			while (env->GetBooleanField(obj, isOpenedField) && !CloseHandle(serialPortHandle) && (numRetries-- > 0));
 			serialPortHandle = INVALID_HANDLE_VALUE;
 			env->SetLongField(obj, serialPortHandleField, -1l);
 			env->SetBooleanField(obj, isOpenedField, JNI_FALSE);
@@ -684,7 +692,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 			// Problem reading, close port
 			int numRetries = 10;
 			PurgeComm(serialPortHandle, PURGE_RXABORT | PURGE_RXCLEAR | PURGE_TXABORT | PURGE_TXCLEAR);
-			while (!CloseHandle(serialPortHandle) && (numRetries-- > 0));
+			while (env->GetBooleanField(obj, isOpenedField) && !CloseHandle(serialPortHandle) && (numRetries-- > 0));
 			serialPortHandle = INVALID_HANDLE_VALUE;
 			env->SetLongField(obj, serialPortHandleField, -1l);
 			env->SetBooleanField(obj, isOpenedField, JNI_FALSE);
@@ -725,7 +733,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_writeBytes(JNIEn
 			// Problem writing, close port
 			int numRetries = 10;
 			PurgeComm(serialPortHandle, PURGE_RXABORT | PURGE_RXCLEAR | PURGE_TXABORT | PURGE_TXCLEAR);
-			while (!CloseHandle(serialPortHandle) && (numRetries-- > 0));
+			while (env->GetBooleanField(obj, isOpenedField) && !CloseHandle(serialPortHandle) && (numRetries-- > 0));
 			serialPortHandle = INVALID_HANDLE_VALUE;
 			env->SetLongField(obj, serialPortHandleField, -1l);
 			env->SetBooleanField(obj, isOpenedField, JNI_FALSE);
@@ -735,7 +743,7 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_writeBytes(JNIEn
 			// Problem reading, close port
 			int numRetries = 10;
 			PurgeComm(serialPortHandle, PURGE_RXABORT | PURGE_RXCLEAR | PURGE_TXABORT | PURGE_TXCLEAR);
-			while (!CloseHandle(serialPortHandle) && (numRetries-- > 0));
+			while (env->GetBooleanField(obj, isOpenedField) && !CloseHandle(serialPortHandle) && (numRetries-- > 0));
 			serialPortHandle = INVALID_HANDLE_VALUE;
 			env->SetLongField(obj, serialPortHandleField, -1l);
 			env->SetBooleanField(obj, isOpenedField, JNI_FALSE);

src/main/java/com/fazecast/jSerialComm/SerialPort.java

@@ -2,7 +2,7 @@
  * SerialPort.java
  *
  *       Created on:  Feb 25, 2012
- *  Last Updated on:  Apr 15, 2019
+ *  Last Updated on:  Jul 08, 2019
  *           Author:  Will Hedgecock
  *
  * Copyright (C) 2012-2019 Fazecast, Inc.
@@ -364,12 +364,14 @@ public final class SerialPort
 	private volatile int baudRate = 9600, dataBits = 8, stopBits = ONE_STOP_BIT, parity = NO_PARITY, eventFlags = 0;
 	private volatile int timeoutMode = TIMEOUT_NONBLOCKING, readTimeout = 0, writeTimeout = 0, flowControl = 0;
 	private volatile int sendDeviceQueueSize = 4096, receiveDeviceQueueSize = 4096;
+	private volatile int rs485DelayBefore = 0, rs485DelayAfter = 0;
 	private volatile SerialPortInputStream inputStream = null;
 	private volatile SerialPortOutputStream outputStream = null;
 	private volatile SerialPortDataListener userDataListener = null;
 	private volatile SerialPortEventListener serialEventListener = null;
 	private volatile String comPort, friendlyName, portDescription;
-	private volatile boolean isOpened = false, disableConfig = false, isRtsEnabled = true, isDtrEnabled = true;
+	private volatile boolean isOpened = false, disableConfig = false;
+	private volatile boolean rs485Mode = false, isRtsEnabled = true, isDtrEnabled = true;
 
 	/**
 	 * Opens this serial port for reading and writing with an optional delay time and user-specified device buffer size.
@@ -820,6 +822,53 @@ public final class SerialPort
 		}
 	}
 
+	/**
+	 * Sets all serial port parameters at one time.
+	 * <p>
+	 * Allows the user to set all port parameters with a single function call.
+	 * <p>
+	 * The baud rate can be any arbitrary value specified by the user.  The default value is 9600 baud.  The data bits parameter
+	 * specifies how many data bits to use per word.  The default is 8, but any values from 5 to 8 are acceptable.
+	 * <p>
+	 * The default number of stop bits is 1, but 2 bits can also be used or even 1.5 on Windows machines.  Please use the built-in
+	 * constants for this parameter ({@link #ONE_STOP_BIT}, {@link #ONE_POINT_FIVE_STOP_BITS}, {@link #TWO_STOP_BITS}).
+	 * <p>
+	 * The parity parameter specifies how error detection is carried out.  Again, the built-in constants should be used.
+	 * Acceptable values are {@link #NO_PARITY}, {@link #EVEN_PARITY}, {@link #ODD_PARITY}, {@link #MARK_PARITY}, and {@link #SPACE_PARITY}.
+	 * <p>
+	 * RS-485 mode can be used to enable transmit/receive mode signaling using the RTS pin. This mode should be set if you plan
+	 * to use this library with an RS-485 device. Note that this mode requires support from the underlying device driver, so it
+	 * may not work with all RS-485 devices.
+	 *
+	 * @param newBaudRate The desired baud rate for this serial port.
+	 * @param newDataBits The number of data bits to use per word.
+	 * @param newStopBits The number of stop bits to use.
+	 * @param newParity The type of parity error-checking desired.
+	 * @param useRS485Mode Whether to enable RS-485 mode.
+	 * @see #ONE_STOP_BIT
+	 * @see #ONE_POINT_FIVE_STOP_BITS
+	 * @see #TWO_STOP_BITS
+	 * @see #NO_PARITY
+	 * @see #EVEN_PARITY
+	 * @see #ODD_PARITY
+	 * @see #MARK_PARITY
+	 * @see #SPACE_PARITY
+	 */
+	public final void setComPortParameters(int newBaudRate, int newDataBits, int newStopBits, int newParity, boolean useRS485Mode)
+	{
+		baudRate = newBaudRate;
+		dataBits = newDataBits;
+		stopBits = newStopBits;
+		parity = newParity;
+		rs485Mode = useRS485Mode;
+
+		if (isOpened)
+		{
+			try { Thread.sleep(200); } catch (Exception e) {}
+			configPort(portHandle);
+		}
+	}
+
 	/**
 	 * Sets the serial port read and write timeout parameters.
 	 * <p>
@@ -1014,6 +1063,33 @@ public final class SerialPort
 		}
 	}
 
+	/**
+	 * Sets whether to enable RS-485 mode for this device.
+	 * <p>
+	 * RS-485 mode can be used to enable transmit/receive mode signaling using the RTS pin. This mode should be set if you plan
+	 * to use this library with an RS-485 device. Note that this mode requires support from the underlying device driver, so it
+	 * may not work with all RS-485 devices.
+	 * <p>
+	 * The delay parameters specify how long to wait before or after transmission of data before enabling or disabling
+	 * transmission mode via the RTS pin.
+	 *
+	 * @param useRS485Mode Whether to enable RS-485 mode.
+	 * @param delayBeforeSendMicroseconds The time to wait after enabling transmit mode before sending the first data bit.
+	 * @param delayAfterSendMicroseconds The time to wait after sending the last data bit before disabling transmit mode.
+	 */
+	public final void setRs485ModeParameters(boolean useRS485Mode, int delayBeforeSendMicroseconds, int delayAfterSendMicroseconds)
+	{
+		rs485Mode = useRS485Mode;
+		rs485DelayBefore = delayBeforeSendMicroseconds;
+		rs485DelayAfter = delayAfterSendMicroseconds;
+
+		if (isOpened)
+		{
+			try { Thread.sleep(200); } catch (Exception e) {}
+			configPort(portHandle);
+		}
+	}
+
 	/**
 	 * Gets a descriptive string representing this serial port or the device connected to it.
 	 * <p>