Android 9 pairing failure

[Nahom]

NRF5_SDK_15.2.0

I am run my android code on android 9 and android 7. Unfortunately my android 9 is paired sometimes and not paired sometimes. especial after i tried to connect for three or four times it get paired. some times it get paired at first try. But I have no this issue with android 7. My Android 7 get connected (paired) with no problem. what can be the problem?

[Sigurd]

Hi,

Do you have any peer manager nrf_logs for when this happens?

Could you do a nRF Sniffer v2 trace to see what is happening on-air?

[Nahom]

I installed nrf connect for mobile app on my android  9 and tried it to connect to my ble module. But it gave me the same issue (some times it is connected and sometimes not connected). but when i try my NRF connect app from my laptop and my iPhone. They are simply connected and disconnected with no problem. Even my android code running on my android 7 also connected and disconnected with no problem. So does android 9 has Bluetooth connection problem or what else.?

here is a picture of my nrf connect which is running on my android 9

[hmolesworth]

We have found that there appears to be a bug in Android 9 BLE in that a scan must be performed before a connection is attempted; at least that fixed our issue when porting the App to Android 9 - started scanning before connecting

[Sigurd]

Nahom said:

So does android 9 has Bluetooth connection problem or what else.?

Some lesser known Android 9 phones might have interoperability issues(the phone is not following Bluetooth spec). What phone brand and model are you using ? If you have an extra nRF52-DK, could you capture a sniffer log?