s110 connection parameters negotiation

RE: s110 connection parameters negotiation

Martin Roa Villescas — Wed, 09 Nov 2016 13:53:33 GMT

This is the criteria that is used in ble_conn_params.c to decide if a connection parameter update request is started or not:

    // Check if interval is within the acceptable range.
    // NOTE: Using max_conn_interval in the received event data because this contains
    //       the client's connection interval.
    if (
        (p_conn_params->max_conn_interval >= m_preferred_conn_params.min_conn_interval)
        &&
        (p_conn_params->max_conn_interval <= m_preferred_conn_params.max_conn_interval)
       )

Therefore, the best way to avoid starting a connection parameter update request is to define the minimum m_preferred_conn_params.min_conn_interval and maximum m_preferred_conn_params.max_conn_interval allowed by the BLE standard for your peripheral device, i.e.:

#define MIN_CONN_INTERVAL               MSEC_TO_UNITS(7.5, UNIT_1_25_MS)
#define MAX_CONN_INTERVAL               MSEC_TO_UNITS(4000, UNIT_1_25_MS)

RE: s110 connection parameters negotiation

Wojtek — Fri, 08 Aug 2014 11:27:38 GMT

It turned out that was not good idea to replace the code as you said.

My application uses other timers and while receiving events such as gap disconnect, the m_conn_params_timer_id code that wasn't removed messed up with my timer (actually it stopped it). So i just set min/max connection parameters same on central and peripheral.

RE: s110 connection parameters negotiation

Stefan Birnir Sverrisson — Thu, 24 Jul 2014 11:26:48 GMT

To not send any connection parameter update request to the central, simply don't create the timer that triggers the connection parameter update request. Do that by replacing

return app_timer_create(&m_conn_params_timer_id, APP_TIMER_MODE_SINGLE_SHOT, update_timeout_handler);

with

return NRF_SUCCESS;

in ble_conn_params_init function in the ble_conn_params.c file.