ble_app_uart can't disconnect/reconnect

[Hugo]

Hello,

on SDK16, with nrd52dk, with android phone, standard ble_app_uart example works fine with nRF Toolbox. But when I disconnect from nrf52dk, the chip still thinks the phone is connected, and even still send data (to nothing).
Is it a normal behaviour?
Kind regards,

[Einar Thorsrud]

Hi,

You should see the link disconnected on the nRF side as well. If it received a disconnect command from the phone, it will show up as disconnected immediately. If not, the nRF will see the link as disconnected after a supervision timeout.

The nRF (SoftDevice) will not continue to send data to nothing (other than retransmissions up to the supervision timeout), so I suspect it is either connected to something else, or your phone did not disconnect after all. A sniffer trace would show clearly which device the nRF communicates with, and in what way (if there really has been a disconnect, or if the phone continue to ack packets).

[Hugo]

Hi,

thank you for your answer, I just test to disable bluetooth too, and when I disable it, the chip "disconnect" too, and advertise again.
So the problem seems to be on nRF Toolbox for BLE 2.8.0, on android 10 updated, Samsung SM-N770F/DS.
I don't have a sniffer to check it.

[Einar Thorsrud]

I see. That makes sense. I am no mobile developer, but it seems Android (like iOS) will not necessarily disconnect even though the app closes the connection.