Pair Device with Legacy Connection OOB preshared key, using Android NRF connect

[Beldramma]

Hi,

I am working on NRF52832-based board, with SDK 15.2.

My BLE device is protected with Legacy Connection OOB preshared key.

I would like to use Android NRF Connect app to pair with my device, filling my OOB key.

I can be in pairing mode and fill my key in NRF Connect Desktop, but not with NRF Connect app.

I don't find any button to do that. There is only a button to bond, so I have added the bonding mode in my application, but I haven't succeeded to bond also.

DO you know how I can pair with my security parameters ? If I can do it only through bonding mode, can you help me resolve my problem ?

I have already checked these others subjects, but they haven't succeeded too :

https://devzone.nordicsemi.com/f/nordic-q-a/47932/oob-works-with-mcp-but-fails-with-nrf-connect

https://devzone.nordicsemi.com/f/nordic-q-a/60196/how-to-enter-oob-key-in-nrf-connect-app

https://devzone.nordicsemi.com/f/nordic-q-a/43338/android-pairing-without-bonding---nrf-connect/172332#172332

Thanks

[daviddedwin]

nRF Connect Desktop on the PC  is Nordicsemi controlled software infrastructure so all the BLE capability should be available for development and test, however  BLE apps on Android will have to use the Android Bluetooth API and its restrictions.
You can also try to get the development working with JUSTWORKS/PASSKEY and then focus on the OOB issue after that so that there are no other issues complicating the development.

[Simonr]

Hi

Beldramma said:

is it normal that i can see my device with NRF COnnect but not with the Bluetooth Common Settings

That depends on what kind of device is advertising. The Bluetooth settings will be able to find some advertising devices, like HID devices, headphones, heart rate measurers, etc. So it depends on what your device advertises as, while the nRFConnect app has no filter by default, and will show any device advertising over BLE.

Best regards,

Simon

[Beldramma]

Hi Simonr,

Simonr said:

That depends on what kind of device is advertising. The Bluetooth settings will be able to find some advertising devices, like HID devices, headphones, heart rate measurers, etc. So it depends on what your device advertises as, while the nRFConnect app has no filter by default, and will show any device advertising over BLE.

I have changed the GAP appearance, but my device is not detected. Maybe the reason is because I have not put any flags in my advertising frame. I have removed them because in my case the data in Manufacturer data and the one from the Name  already reach 31 bytes, the maximum Advertising length.

[Beldramma]

daviddedwin said:

You can also try to get the development working with JUSTWORKS/PASSKEY and then focus on the OOB issue after that so that there are no other issues complicating the development.

For now, i deactivate the security part to test others parts.

[Simonr]

Beldramma said:

Maybe the reason is because I have not put any flags in my advertising frame

 That seems likely. The phone OS'es (Android and iOS) won't "detect" devices that don't add the general discoverable flag and/or include appearance in the advertising_init() function like below:

 init.advdata.include_appearance = true;

Best regards,

Simon