How to handle a sudden disconnection of the master on the peripheral (NRF8001)

[Omnia]

Hello Nordic team,

I am working on a BLE RedBearLab shield (nrf8001) mounted on an Arduino board.

Consider that a connection is correctly made from a Master app to my nrf8001 (Peripheral) . The master have already subscribed to an advertising characteristic (with a notify mod) and every thing is fine.

If the Master suddenly stop running (for exemple if the Master is out of battery or just crashed…) I would like to know the proper way to inform my nrf8001 board that the subscription of the advertising characteristic previously made is not valid anymore.

How can I do that ? My first idea was to sent a packet every X period of time from my peripheral board with an acknowledgement and if I haven’t received any response before a pre-determined time , I can consider that the connection is lost. Is there any other/better way to do that ? How can I know that there is no more valid connection on the peripheral side?

Thanks, Regards,

[David Edwin]

You are using the ble_heart_rate_template , this means that you are not using any encryption on the link. This also means that as soon as the ACI Disconnected Event is received, all subscriptions for Notify and Indicate are cancelled. This means that the next time the master connects, she will have to subscribe again to the Characteristics that are Notify or Indicate. When the master subscribes, a ACI Pipe Status Event will be received that shows that the specific Notify pipe is available. The subscription has to be done for every connection from the master when encryption is not used.

In short: The ACI Disconnected Event can act as the way to signal that the app has finished.

I hope this helps.