Hi I done a android app and I need to print recieps, I am connection the printer via USB to the android tablet an sending a basic message
 
String tmpHeader = "^XA"+ "^FO50,50^ADN,36,20^FDxxxxxxxxxxx^FS"+ "^XZ";
 
  arregloBytes = tmpHeader.getBytes();
 
 
 
   public void startPrinting(final UsbDevice printerDevice)
 
  {
   Handler handler = new Handler();
   handler.post(new Runnable()
  {
   UsbDeviceConnection conn;
   UsbInterface usbInterface;

   //@RequiresApi(api = Build.VERSION_CODES.N)
   @Override
   public void run()
  {
   try
  {
   for (int i = 0; i printerDevice.getInterfaceCount(); i++)
  {
  usbInterface = printerDevice.getInterface(i);
  }
   UsbEndpoint endPoint = usbInterface.getEndpoint(0);
  conn = mUsbManager.openDevice(mDevice);
   conn.claimInterface(usbInterface, true);
   //conn.bulkTransfer(endPoint, arregloLogo, arregloLogo.length, 0);
   conn.bulkTransfer(endPoint, arregloBytes, arregloBytes.length, 0);
   mPromise.resolve(arregloBytes.toString());
  mPromise = null;
   conn.close();
  
  }
   catch (Exception e)
  {
   mPromise.reject(e);
  mPromise = null;
   Log.e("Exception", "Unable to transfer bulk data");
   e.printStackTrace();
  }

  }
  });
  }

 
the response is successful but it doesn't print anything.
 
I use the same code from printing in other printer and it works perfectly
thank you for your help