jav通过串口读取数据

灰太狼 2021-12-05 15:39 272阅读 0赞

### **1、要知道串口是多少，波特率是多少** ###

**串口是COM3；波特率115200；**

**串口是可以通过以下方式查看的；**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTkxNjM3_size_16_color_FFFFFF_t_70][]

### **2、通过COMMIX助手先测试是否能接受得到数据** ###

**2.1、串口对应的是COM3**

**2.2、波特率是115200；**

**2.3、打开串口，如果可以接受数据，那么说明你的设备没有问题**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTkxNjM3_size_16_color_FFFFFF_t_70 1][]

### 下载包，并且配置 ###

[https://download.csdn.net/download/qq\_37591637/11391715][https_download.csdn.net_download_qq_37591637_11391715]

### **3、java程序如下** ###

package cn.com.com;
    import gnu.io.*;
    import java.io.IOException;
    import java.io.InputStream;
    import java.util.Enumeration;
    import java.util.TooManyListenersException;
    /*
     * java串口通讯
     * Created by DELL on 2017/4/24.
     */
    public class SerialPortUtils implements SerialPortEventListener {
    
        private static final String DEMONAME = "串口测试";
    
        /**
         * 检测系统中可用的端口
         */
        private CommPortIdentifier portId;
        /**
         * 枚举类
         */
        private Enumeration portList;
        /**
         * 输入流
         */
        private static InputStream inputStream;
        /**
         * RS-232的串行口
         */
        private SerialPort serialPort;
        /**
         * 串口返回信息
         */
        private static String test = "";
    
        /**
         * 初始化
         *
         * @param baudRate 波特率
         */
        public void init(int baudRate) {
            //获取系统中可用的端口
            portList = CommPortIdentifier.getPortIdentifiers();
            while (portList.hasMoreElements()) {
                portId = (CommPortIdentifier) portList.nextElement();
                if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL && portId.getName().equals("COM3")) {
                    System.out.println("发现端口："+portId.getName());
                    try {
                        serialPort = (SerialPort) portId.open(DEMONAME,2000);
                        //设置串口监听
                        serialPort.addEventListener(new SerialPortUtils());
                        //设置开启监听
                        serialPort.notifyOnDataAvailable(true);
                        //设置波特率、数据位、停止位、检验位
                        serialPort.setSerialPortParams(baudRate,
                                SerialPort.DATABITS_8,
                                SerialPort.STOPBITS_1,
                                SerialPort.PARITY_NONE);
                        //获取输入流
                        inputStream = serialPort.getInputStream();
                    } catch (PortInUseException e) {
                        e.printStackTrace();
                    } catch (TooManyListenersException e) {
                        e.printStackTrace();
                    } catch (UnsupportedCommOperationException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    
        /**
         * 监听函数
         * @param serialPortEvent
         */
        public void serialEvent(SerialPortEvent serialPortEvent) {
            switch (serialPortEvent.getEventType()) {
                //获取到有效信息
                case SerialPortEvent.DATA_AVAILABLE :
                    readComm();
                    break;
                default:
                    break;
            }
        }
    
        /**
         * 读取串口信息
         */
        private void readComm() {
            byte[] readBuffer = new byte[15];
            try {
                int len = 0;
                while ((len = inputStream.read(readBuffer)) != -1) {
                    test += new String(readBuffer,0, len).trim();
                    break;
                }
                StringBuilder sb=new StringBuilder();
                for (byte b : readBuffer) {
                	String a="";
                    if (b < 0) {
                        //byte的范围是-128到+127
                        int i = 128 + (int) b + 127 + 1;
                        //转换成16进制
                        a=Integer.toHexString(i);
                        
                    }else {
                    	a=Integer.toHexString(b);
                    }
                    if(a.length()==1){
                    	a="0"+a;
                    }
                    sb.append(a);
                }
                System.out.println("接收的数据:"+sb);
            } catch (IOException e) {
                e.printStackTrace();
            }
    
        }
    
        private void close() {
            serialPort.close();
        }
    
         public static void main(String[] args) {
        	 //波特率的设置
            new SerialPortUtils().init(115200);
        }
    }

### **运行效果如下** ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTkxNjM3_size_16_color_FFFFFF_t_70 2][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTkxNjM3_size_16_color_FFFFFF_t_70]: /images/20211205/091668131bad46d686303359d3cba32c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTkxNjM3_size_16_color_FFFFFF_t_70 1]: /images/20211205/5006e598bda844fe91b9b0a3bb99daa7.png
[https_download.csdn.net_download_qq_37591637_11391715]: https://download.csdn.net/download/qq_37591637/11391715
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTkxNjM3_size_16_color_FFFFFF_t_70 2]: /images/20211205/71fe9c1b4d5f4e24870e9aacb187407b.png