Bluetooth shield 2.0 paring issue after device is reset

Hi, I bought Seeed bluetooth shield 2.0, add it on Leonardo, and successfully made it connect to my PC with Windows 10 installed.

My PC finds the bluetooth module well and I can get data from Leonardo using serial port. Everything is fine.

Here is my question - when I turn off Leonardo and turn it on again, serial communication via SPP is not possible.

I have to manually remove the corresponding BT device in BT device management console of Windows 10 and reconnect the device. In other words, I have to pair the device to PC every time it is powered on. This behavior is not convenient and I want to know how to resolve this issue. As far as I know, most commercial BT devices do not suffer from this issue.

This problem does not happen when BT device (BT shield + Leonardo) is turned on and I reboot my PC.

The code below is what I used to initialize BT shield.



  blueToothSerial.print("AT+DEFAULT"); // Restore all setup value to factory setup

  blueToothSerial.print("AT+NAMESeeedBTSlave"); // set the bluetooth name as "SeeedBTSlave" ,the length of bluetooth name must less than 12 characters.

  blueToothSerial.print("AT+PIN0000"); // set the pair code to connect


After this “factory initialization” I don’t use the above code in my firmware since BT shield remember these settings.

After hours of googling, I test the following code since it seems to make BT shield to auto connect to the last connected device when powered on. But not difference.


Any insight/tips would be greatly appreciated.



I checked the datasheet of the BLE module used in the Shield, there is no STAUTO command supported. The initiation for the connection should come from PC (OS). I think for Seial Port Profile, we might need to reconnect if the connection is lost.

Also check the AT commands in the data-sheet and try using master mode.