The working principle of RXTX serial and parallel I/O library in the Java class library

The working principle of RXTX serial and parallel I/O library in the Java class library Brief introduction RXTX is a Java class library for serial and parallel I/O operations, which provides the ability to communicate with hardware.Whether it is connecting sensors, reading or writing data, controlling robots or other serial communication, the RXTX library can help us implement these operations.This article will introduce the working principle of RXTX serial and parallel I/O libraries in the Java class library, and provide some example code to help readers better understand. working principle The core of the RXTX library is a Native interface, which allows Java applications to directly call the underlying system operation to complete the serial and parallel I/O operation.The Native interface is written in C/C ++ so that Java can use the I/O function of the underlying system. To use the RXTX library, you need to download and install the RXTX library file first.Then add these library files to your Java project.Next, you need to import the `gnu.io` package, which contains all the classes and interfaces of the RXTX library. Once you are ready, you can use the class and interfaces in the RXTX library for serial and parallel I/O operation.Here are some commonly used classes and interfaces: 1. CommPortIdIdifier`: This class indicates a identifier of a serial or parallel communication port.You can use it to obtain the available communication port lists, turn on and off port. 2. `Serialport`: This class represents an open serial port.You can use it for reading and writing operations to control serial communication parameters such as data bit, stopping, and verification. 3. `Parallelport`: This class represents an open port.Similar to Serialport, you can use it for reading and writing operations, and control parallel communication parameters. The following is a simple example code that shows how to use the RXTX library to open and read the data on the serial port: import gnu.io.*; public class SerialPortExample { public static void main(String[] args) { CommPortIdentifier portId; SerialPort serialPort; try { // Get the serial port identifier portId = CommPortIdentifier.getPortIdentifier("/dev/ttyUSB0"); // Open the serial port serialPort = (SerialPort) portId.open("SerialPortExample", 2000); // Configure serial port parameters serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); // Get the input stream InputStream inStream = serialPort.getInputStream(); // Read the data in the input stream byte[] buffer = new byte[1024]; int bytesRead = inStream.read(buffer); // Output read data System.out.println("Received data: " + new String(buffer, 0, bytesRead)); // Turn off the serial port serialPort.close(); } catch (Exception e) { e.printStackTrace(); } } } In the above example, we first obtained the identifier of the serial port by calling the method by calling the `Commodidentifentifier.GetPortIdifier ()" method.Then, we use this identifier to open the serial port and use the method of the serial port with the method of `setSerialportparams ()`.Next, we obtained the input stream of the serial port and read data from it.Finally, we closed the serial port.Please note that this is just a simple example. In practical applications, more logic may need to process data. in conclusion RXTX serial and parallel I/O libraries provide the ability to communicate with hardware in Java applications.It uses the I/O function of the underlying system to achieve serial and parallel I/O operations.By using the RXTX library, we can easily communicate with serial and parallel devices, and read and write data as needed.I hope this article will help you understand the working principle of RXTX serial and parallel I/O libraries. Reference materials: - [RXTX Wiki](https://rxtx.qbang.org/wiki/index.php/Main_Page) - [RXTX Java API Documentation](https://rxtx.qbang.org/wiki/index.php/API_Documentation)