Question

我正在开发一个需要与连接usb-to-rs232转换器的终端通信的java应用程序!!

现在我可以连接设备并发送数据！我可以确定终端收到发送的数据，因为当终端收到东西时LED发光！

我正在使用JSSC（链接：https://code.google.com/p/java-simple-serial-connector/wiki/jSSC_examples）...但由于某种原因，我永远不会永远不会从终端接收任何数据。

我的代码（JSSC代码）：

public class Main
{

    static SerialPort serialPort;

    public static void main(String[] args) throws InterruptedException
    {
        serialPort = new SerialPort("COM7"); 
        try
        {
             serialPort.openPort();//Open port
             serialPort.setParams(9600, 8, 1, 0);//Set params
             int mask = SerialPort.MASK_RXCHAR + SerialPort.MASK_CTS + SerialPort.MASK_DSR;//Prepare mask
             serialPort.setEventsMask(mask);//Set mask
             serialPort.addEventListener(new SerialPortReader());//Add SerialPortEventListener

             serialPort.writeByte( (byte)0x02 );

             TimeUnit.SECONDS.sleep( 10 );

             byte[] b = serialPort.readBytes();
             System.out.println( "bytes " + b );
        }
        catch (SerialPortException ex)
        {
             System.out.println(ex);
        }
}

/*
 * In this class must implement the method serialEvent, through it we learn about 
 * events that happened to our port. But we will not report on all events but only 
 * those that we put in the mask. In this case the arrival of the data and change the 
 * status lines CTS and DSR
 */
static class SerialPortReader implements SerialPortEventListener
{
    public void serialEvent(SerialPortEvent event)
    {
         System.out.println( "Event raised!" );
         if(event.isRXCHAR())
         {//If data is available
              if(event.getEventValue() == 10)
              {//Check bytes count in the input buffer
              //Read data, if 10 bytes available 
                   try
                   {
                        byte buffer[] = serialPort.readBytes(10);
                   }
                   catch (SerialPortException ex)
                   {
                        System.out.println(ex);
                   }
              }
         }
         else if(event.isCTS())
         {//If CTS line has changed state
              if(event.getEventValue() == 1)
              {//If line is ON
                  System.out.println("CTS - ON");
              }
              else
              {
                   System.out.println("CTS - OFF");
              }
         }
         else if(event.isDSR())
         {///If DSR line has changed state
              if(event.getEventValue() == 1)
              {//If line is ON
                  System.out.println("DSR - ON");
              }
              else
              {
                   System.out.println("DSR - OFF");
              }
         }
    }
}
}

任何人都可以帮我解决这个问题吗？

Answer 1

您是否打算使用USB-UART进行硬件流控制？如果是，请尝试设置DTR，然后设置RTS。这告诉第一端，第二端已准备好进行通信。还没有接收到10个字节或者根本没有接收到数据。还要考虑另一个串口通信库，如scm http://www.embeddedunveiled.com/

从连接USB-> RS232的终端接收数据

1 个答案: