Recommended configuration for data length extension + multiple connections

[Youssif]

Hi

The concept of setting the event_length (the time set aside per connection) was introduced post softdevice v3.0.0. To my understanding, with softdevice v3.0.0, the softdevice dynamically sets the time allocated per connection depending on the number of connections. My questions are:-

1. Is it possible to replicate this behavior for the current version (v5.0.0) of the softdevice?
2. What is the relation (if any) between 'event_length' and 'connection interval'?
3. What is the recommended configuration for achieving both data length extension and 8+ connections?

To give some context, we are currently trying to write an app which is capable of both: data length extension and 8 simultaneous connections+pairings. We are therefore setting our event_length to 320 (i.e. 400ms for data length extension and high throughput) and our conn_count to 8 when enabling the softdevice. Everything works fine and we don't get any errors when enabling the softdevice. However, when we try to pair with the connected devices, the pairing process fails. This looks to be a timing issue because successful pairing is performed over several connection intervals. When we change our event_length to BLE_GAP_EVENT_LENGTH_DEFAULT (3), the process succeeds without an issue. Also, the same process succeeds on v3.0.0 of the softdevice.

We are using softdevice S132 v5.0.0 on an nrf52832 chip.

Thanks