nRF52840 in multirole (Central and Peripheral)

[bojan]

Hello guys,

We are developing nRF52840-based device that needs to act as both BLE Central and Peripheral.

Peripheral role:

In BLE Peripheral mode, nRF52840 should advertise with whitelisting allowing only BLE Centrals with particular short device name to establish BLE connection. Moreover, we would like to have the ability to break BLE connection from the Periperal side (nRF52840 acting as a peripheral to initiate BLE disconnect) after some timeout. We don't want any pairing and bonding while establishing BLE connection (we will encrypt our data while transferring over BLE).

Central role:

In BLE Central mode, nRF52840 would scan with whitelisting looking for advertisement packets from BLE Peripherals with particular short device name. We are still not sure, but it can happen that we would need to send BLE Scan Request upon detection of BLE Advertising Data packet. There will be no BLE connection between nRF52840 BLE Central and BLE Peripheral devices in this mode.

Quesitons:

1.  Is ble_app_multirole_lesc example from examples/ble_central_and_peripheral_experimental the best project to start with?
2. This project contains LE Security Connection (LESC) part that we want to get rid of. What would be needed to remove that part, should we exclude peer_manager_init()function from the code or at least its pm_sec_params_set(&sec_params) part?
3. Is it possible for nRF52840 as BLE Peripheral to somehow limit the duration of the BLE connection?
4. Any example where we can see how to send Scan Request from nRF52840?

Thank you very much for your time and efforts. It is really appreciated.

Cheers,

Bojan.

[bojan]

Is it possible to use conn_sup_timeout parameter from ble_gap_conn_params_t structure (Connection Supervision Timeout in 10ms units) to automatically limit the duration of BLE connection from within gap_params_init function?

[Kenneth]

The supervisor timeout only control how long time after the two devices are out of range of each other before they should consider link is lost.

Kenneth

[bojan]

Got it!

Thanks Kenneth.

I would need to include the timer and disconnect explicitly with sd_ble_gap_disconnect() function in that case.

Bojan.