求教Android蓝牙串口开发OutputStream发送数据失败

Question

各位大佬，我最近和队友一起在做安卓蓝牙与嵌入式系统蓝牙模块的通信，嵌入式端经测试能够正常接收和发送数据，安卓端也能够正常接收嵌入式端发送的数据，但在安卓端向嵌入式端发送数据时嵌入式端没有接收到数据，但安卓端也没有报错，求大佬支招！

Answer 1

安卓端数据发送代码如下：
private void sendMessageHandle(final String msg)
    {
        if (mSocket == null)
        {
            Toast.makeText(this, "未连接到设备", Toast.LENGTH_SHORT).show();
            return;
        }
        mBluetoothAdapter.cancelDiscovery();
        if(mSocket.isConnected()){
            try {
                OutputStream os = mSocket.getOutputStream();
                os.write(hexStringToBytes(msg));
                os.flush();
                os.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }else{
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        mSocket.connect();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }).start();
            try {
                OutputStream os = mSocket.getOutputStream();
                os.write(hexStringToBytes(msg));
                os.flush();
                os.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }    }