nrf52832 DFU persistent bonding information

[Andreas3T]

Hi,

We have a project which is based on the example buttonless DFU and I'm currently testing the persistence of the bonding information between nRF and the external BLE device. It works as expected but reading out the memory address of the FDS location I can see that for every time we connect a new entry is made. Should this be the case? An entry is created only once for each paired device.

What happens when the FDS memory is filled?

Best Regards,
Andreas

[Jørgen Holmefjord]

Hi,

When you are bonded, the peer will store GATT cache information to remember the state of Client Characteristic Configuration Descriptor (CCCD), etc. This will allow the device to automatically restore the state when a new connection is made to the bonded peer. Peer manager will update the record if there are some change to the stored parameters.

The following things may cause records to be updated:

• PM_PEER_RANKS
• PM_SERVICE_CHANGED
• PM_PEER_DATA_ID_BONDING
• PM_PEER_DATA_ID_CENTRAL_ADDR_RES
• PM_PEER_DATA_ID_GATT_LOCAL

I'm not sure exactly what is changed in your case, without having a look at the records.

When all pages allocated for FDS is full, peer manager will start garbage collection, to free the space occupied by invalidated records.

Best regards,
Jørgen