无法连接到蓝牙模块

Question

本周末，我决定与arduino合作。目前我在将手机连接到Arduino时遇到了困难。我已成功将模块的地址传递给ledControl.java。我正在使用AsyncTask来执行连接到arduino的操作。任何人都可以指导我。
注意：m无法连接任何具有蓝牙功能的设备。

import android.app.Activity;
import android.app.ProgressDialog;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.SeekBar;
import android.widget.Toast;

import java.io.IOException;
import java.util.UUID;

/**
 * Created by milind on 09/01/16.
 */
public class ledControl extends Activity {


Button btnOn, btnOff, btnDis;
SeekBar brightness;
String address = null;
private ProgressDialog progress;
BluetoothAdapter myBluetooth = null;
BluetoothSocket btSocket = null;
private boolean isBtConnected = false;
static final UUID myUUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.led_control);
    //receive the address of the bluetooth device
    Intent newint = getIntent();
    address = newint.getStringExtra("address");
    Log.wtf("ledControl Address:", address); // Log value received.

    //view of the ledControl layout
    //call the widgtes
    btnOn = (Button) findViewById(R.id.on);
    btnOff = (Button) findViewById(R.id.off);
    //btnDis = (Button)findViewById(R.id.button4);
    //brightness = (SeekBar)findViewById(R.id.seekBar);
    new ConnectBT().execute(address);

    btnOn.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v)
        {
            turnOnLed();      //method to turn on
        }
    });

    btnOff.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v)
        {
            turnOffLed();   //method to turn off
        }
    });
}
private void turnOffLed()
{
    if (btSocket!=null)
    {
        try
        {
            btSocket.getOutputStream().write("1".toString().getBytes());
        }
        catch (IOException e)
        {
            msg("Error");
        }
    }
}
private void turnOnLed()
{
    if (btSocket!=null)
    {
        try
        {
            btSocket.getOutputStream().write("2".toString().getBytes());
        }
        catch (IOException e)
        {
            msg("Error");
        }
    }
}


    private class ConnectBT extends AsyncTask<String, Void, Void>  // UI thread
    {
        private boolean ConnectSuccess = true; //if it's here, it's almost connected


        @Override
        protected void onPreExecute()
        {
            Log.i("ledControl","Device Connecting");
            //progress = ProgressDialog.show(ledControl.this, "Connecting...", "Please wait!!!");  //show a progress dialog
        }

        @Override
        protected Void doInBackground(String... devices) //while the progress dialog is shown, the connection is done in background
        {
            try
            {
                if (btSocket == null || !isBtConnected)
                {

                    Log.wtf("ledControl","AsyncTask Called");
                    myBluetooth = BluetoothAdapter.getDefaultAdapter();//get the mobile bluetooth device
                    Log.wtf("AsyncTask:",address);
                    BluetoothDevice dispositivo = myBluetooth.getRemoteDevice(devices[0]);//connects to the device's address and checks if it's available
                    btSocket = dispositivo.createInsecureRfcommSocketToServiceRecord(myUUID);//create a RFCOMM (SPP) connection
                    BluetoothAdapter.getDefaultAdapter().cancelDiscovery();
                    btSocket.connect();//start connection
                    Log.i("ledControl:","Connected to Device.");
                }
            }
            catch (IOException e)
            {
                ConnectSuccess = false;//if the try failed, you can check the exception here
            }
            return null;
        }
        @Override
        protected void onPostExecute(Void result) //after the doInBackground, it checks if everything went fine
        {
            super.onPostExecute(result);

            if (!ConnectSuccess)
            {

                msg("Connection Failed. Is it a SPP Bluetooth? Try again."); // This toast is produced everytime.
                finish();
            }
            else
            {
                msg("Connected.");
                isBtConnected = true;
            }
            //progress.dismiss();
        }
    }



private void msg(final String s)
{
    runOnUiThread(new Runnable() {
        @Override
        public void run() {
            Toast.makeText(getApplicationContext(), s, Toast.LENGTH_LONG).show();

        }
    });
}
}

最后，我得到了这个Toast消息。 “连接失败。它是SPP蓝牙吗？再试一次。”