Question

我尝试使用InputStream从我的Arduino接收数据，但出于某种原因我将其作为输出。

àààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààààà

这是我接收数据的代码：

package midistep;
import gnu.io.CommPort;
import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;

import java.io.BufferedReader;
import java.io.FileDescriptor;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;

public class TwoWaySerialComm
{
    public OutputStream out1;
    public TwoWaySerialComm()
    {
        super();
    }

    void connect ( String portName ) throws Exception
    {
        CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
        if ( portIdentifier.isCurrentlyOwned() )
        {
            System.out.println("Error: Port is currently in use");
        }
        else
        {
            CommPort commPort = portIdentifier.open(this.getClass().getName(),2000);

            if ( commPort instanceof SerialPort )
            {
                SerialPort serialPort = (SerialPort) commPort;
                serialPort.setSerialPortParams(57600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);

                InputStream in = serialPort.getInputStream();
                OutputStream out = serialPort.getOutputStream();
                out1=out;
                (new Thread(new SerialReader(in))).start();
                (new Thread(new SerialWriter(out))).start();

            }
            else
            {
                System.out.println("Error: Only serial ports are handled by this example.");
            }
        }     
    }

    /** */
    public static class SerialReader implements Runnable 
    {
        InputStream in;

        public SerialReader ( InputStream in )
        {
            this.in = in;
        }

        public void run ()
        {
            byte[] buffer = new byte[1024];
            int len = -1;
            try
            {
                while ( ( len = this.in.read(buffer)) > -1 )
                {
                    System.out.print(new String(buffer,0,len));
                }
            }
            catch ( IOException e )
            {
                e.printStackTrace();
            }            
        }
    }

    /** */
    public static class SerialWriter implements Runnable 
    {
        public OutputStream out;

        public SerialWriter ( OutputStream out )
        {
            this.out = out;
        }

        public void run ()
        {
            try
            {                
                int c = 0;
                while ( ( c = System.in.read()) > -1 )
                {
                    this.out.write(c);
                }                
            }
            catch ( IOException e )
            {
                e.printStackTrace();
            }            
        }
    }
    public void writetoport(int Steps) {

        try {
                out1.write(Steps);
                out1.flush();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
    }
    public static void main ( String[] args )
    {
        try
        {
            (new TwoWaySerialComm()).connect("COM3");
        }
        catch ( Exception e )
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

我的Arduino代码：

int received = 0;
void setup() {
  Serial.begin(9600);
  pinMode(LED_BUILTIN, OUTPUT);
}

void loop() {
  delay(1000);
  Serial.println("Hello world");
  if (Serial.available() > 0) {
    received = Serial.read();
    if (received > 1000) {
      int speed = received;
      String tempstring = String(speed);
      tempstring.substring(1);
      speed = tempstring.toInt();
      Serial.println("gotit" + speed);
    }
    else if (received = 1) {
      Serial.print("I received something >");
      Serial.print(received);
      Serial.println("<");
      digitalWrite(LED_BUILTIN, HIGH);
      delay(1000);
      digitalWrite(LED_BUILTIN, LOW);
    }
  }
}

希望这是一个简单的问题。谢谢

Answer 1

您设置了错误的波特率。你的Java代码有

 serialPort.setSerialPortParams(57600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);

但是你的Arduino草图中有

 Serial.begin(9600);

波特率必须相同，否则会出现传输错误。

InputStream打印奇怪的字符

1 个答案: