Use NUS Service on bonded devices without discovery

[BjoernSchmitz]

Hi,

I am developing a system with 2 nrf52840 devices, communicating via the NUS Service. I am programming both the central and peripheral project. I am using the NRF5 SDK with S140 Softdevice on both sides.

I am trying to speed up the connection procedure as far as possible. Therefore, I bond both devices. I know that characteristics, that are notified on bonded devices, stay notified the next time they connect. It seems to work, since I can skip "ble_nus_c_tx_notif_enable()" for bonded device and still receive value notifications on the TX characteristic. However, the NUS event handler is not called before I call "ble_nus_c_on_db_disc_evt()".

The problem is that characteristic discovery takes to long for my application. Thus, I would like to directly start communicating with bonded devices, without discovery. Is there a way to do that? Do I have to call  ble_nus_c_on_db_disc_evt with the parameters read from the peer manager (e.g. by using pm_peer_data_remote_db_load()).

Thank you and best regards

Bjoern

[Simonr]

Thank you for your clarification Björn!

The reason the MTU negotiation is initialized upon connection is that the ble_conn_params.c file starts this negotiation for you upon a connected event. In order to skip/avoid the MTU negotiation, you can remove the ble_conn_params.c file from your project. Keep in mind that there are some other functions in this file as well that you'll miss out on.

Best regards,

Simon

[BjoernSchmitz]

Ok, thanks. I will try that.