如何将android中的串口通信的波特率从19200改为115200

Question

我是android的新手。我正在开发一个Android和PC之间的串行通信应用程序，我在这里做了一些代码，用于将一些数据从android连续发送到PC。但它正在使用19200的波特率，但我想要115200.我曾经把波特率控制转移的速率值，但它不适用于我请帮助我如何使用115200波特率从android到PC串行发送数据

这就是我用波特率115200所做的，但它适用于19200：

package com.medeQuip.communication;

import java.nio.ByteBuffer;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.hardware.usb.UsbConstants;
import android.hardware.usb.UsbDevice;
import android.hardware.usb.UsbDeviceConnection;
import android.hardware.usb.UsbEndpoint;
import android.hardware.usb.UsbInterface;
import android.hardware.usb.UsbManager;
import android.hardware.usb.UsbRequest;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.ToggleButton;

public class MainActivity extends Activity implements Runnable{

 private static final String TAG = "MedeQuip Demo Communication";

 private static final byte IGNORE_00 = (byte) 0x00;
 ToggleButton buttonLed;
 EditText textOut;
 Button buttonSend;
 TextView textIn;

 String stringToRx;

 private UsbManager usbManager;
    private UsbDevice deviceFound;
    private UsbDeviceConnection usbDeviceConnection;
    private UsbInterface usbInterfaceFound = null;
 private UsbEndpoint endpointOut = null;
 private UsbEndpoint endpointIn = null;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);



  textOut = (EditText)findViewById(R.id.textout);
  textIn = (TextView)findViewById(R.id.textin);
  buttonSend = (Button)findViewById(R.id.send);
  buttonSend.setOnClickListener(new OnClickListener(){

   @Override
   public void onClick(View v) {
    final String textToSend = textOut.getText().toString();
    if(textToSend!=""){
     stringToRx = "";
     textIn.setText("");
     Thread threadsendArduinoText = 
      new Thread(new Runnable(){

       @Override
       public void run() {
        sendArduinoText(textToSend);
       }});
     threadsendArduinoText.start();
    }

   }});

  usbManager = (UsbManager)getSystemService(Context.USB_SERVICE);
 }

 @Override
    public void onResume() {
        super.onResume();

        Intent intent = getIntent();
        String action = intent.getAction();

        UsbDevice device = (UsbDevice)intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
        if (UsbManager.ACTION_USB_DEVICE_ATTACHED.equals(action)) {
            setDevice(device);
        } else if (UsbManager.ACTION_USB_DEVICE_DETACHED.equals(action)) {
            if (deviceFound != null && deviceFound.equals(device)) {
                setDevice(null);
            }
        }
    }

 private void setDevice(UsbDevice device) {
        usbInterfaceFound = null;
     endpointOut = null;
     endpointIn = null;

        for (int i = 0; i < device.getInterfaceCount(); i++) {         
   UsbInterface usbif = device.getInterface(i);

   UsbEndpoint tOut = null;
   UsbEndpoint tIn = null;

   int tEndpointCnt = usbif.getEndpointCount();
   if (tEndpointCnt >= 2) {
    for (int j = 0; j < tEndpointCnt; j++) {
     if (usbif.getEndpoint(j).getType() 
      == UsbConstants.USB_ENDPOINT_XFER_BULK) {
      if (usbif.getEndpoint(j).getDirection() 
       == UsbConstants.USB_DIR_OUT) {
       tOut = usbif.getEndpoint(j);
      } else if (usbif.getEndpoint(j).getDirection() 
       == UsbConstants.USB_DIR_IN) {
       tIn = usbif.getEndpoint(j);
      }
     }
    }

    if (tOut != null && tIn != null) {
     // This interface have both USB_DIR_OUT
     // and USB_DIR_IN of USB_ENDPOINT_XFER_BULK
     usbInterfaceFound = usbif;
     endpointOut = tOut;
     endpointIn = tIn;
    }
   }
  }

        if (usbInterfaceFound == null) {
            return;
        }

        deviceFound = device;

        if (device != null) {
            UsbDeviceConnection connection = 
             usbManager.openDevice(device);
            if (connection != null && 
             connection.claimInterface(usbInterfaceFound, true)) {

                connection.controlTransfer(0x21, 34, 0, 0, null, 0, 0);
                connection.controlTransfer(0x21, 32, 0x001A, 0, 
                  new byte[] { (byte) 0x80, 0x25, 0x00, 
                   0x00, 0x00, 0x00, 0x08 }, 
                  7, 0);
                usbDeviceConnection = connection;
                Thread thread = new Thread(this);
                thread.start();

            } else {
                usbDeviceConnection = null;
            }
         }
    }

 @SuppressWarnings("unused")
private void sendArduinoCommand(int control) {
        synchronized (this) {

            if (usbDeviceConnection != null) {
                /*String text = textOut.getText().toString();
                byte[] b = new byte[text.length()];
                b = text.getBytes();
                for(int i=0; i< b.length; i++){
                 //b[0] = message[i];
                 //Log.d(TAG, "sendArduinoTextb[0]: " + b[0]);
                 usbDeviceConnection.bulkTransfer(endpointOut,b, b.length, 0);
            }*/
        }
        }
    }

 private void sendArduinoText(String s) {
        synchronized (this) {

            if (usbDeviceConnection != null) {

             Log.d(TAG, "sendArduinoText: " + s);


                /*
                usbDeviceConnection.bulkTransfer(endpointOut,
                  message, message.length, 0);
                */
                String text = textOut.getText().toString();
                byte[] b = new byte[text.length()];
                b = text.getBytes();
               // for(int i=0; i< b.length; i++){
                 //b[0] = message[i];
                 //Log.d(TAG, "sendArduinoTextb[0]: " + b[0]);
                 usbDeviceConnection.bulkTransfer(endpointOut,b, b.length, 0);
                 try {
      Thread.sleep(100);
     } catch (InterruptedException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
     }
               // }
            }
        }
    }

 @Override
 public void run() {
  ByteBuffer buffer = ByteBuffer.allocate(1);
        UsbRequest request = new UsbRequest();
        request.initialize(usbDeviceConnection, endpointIn);
        while (true) {
            request.queue(buffer, 1);
            if (usbDeviceConnection.requestWait() == request) {
                byte dataRx = buffer.get(0);
                Log.d(TAG, "dataRx: " + dataRx);
                if(dataRx!=IGNORE_00){

                 stringToRx += (char)dataRx;
                 runOnUiThread(new Runnable(){

      @Override
      public void run() {
       textIn.setText(stringToRx);
      }});
                }
            } else {
                break;
           }
        }

 }

}