BLE connection error with IOS devices

[QuentinD]

Hello

I'm contacting you because I'm having a problem connecting to devices that use the ble_thread_dyn_mtd_coap_cli example.
Actually, I have no problem when I connect with an Android device but the connection fails if I connect with an IOS device.

I have attached the logs of a Samsung S10 which works well and the logs of an iPhone 12 where I have a problem.

Looking at the logs, I see that in the case of IOS phones, that the smartphone sends the command "LL_PHY_REQ" saying that "Sender prefers to use the LE 2M PHY" and that nothing more happens afterwards ... However, this command is never sent with Android ...

Here are my questions:
- Do you have any idea why it stops responding after received this command?
- Would it be possible to make the smartphone believe that the device is not compatible with the 2M PHY to see if that corrects the problem?

Thank you

NOK-IPhone12-2.pcapngSamsung S10.pcapng

[Kenneth]

Can you try to add the following to ble_evt_handler():

        case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
        {
            NRF_LOG_DEBUG("PHY update request.");
            ble_gap_phys_t const phys =
            {
                .rx_phys = BLE_GAP_PHY_AUTO,
                .tx_phys = BLE_GAP_PHY_AUTO,
            };
            err_code = sd_ble_gap_phy_update(p_ble_evt->evt.gap_evt.conn_handle, &phys);
            APP_ERROR_CHECK(err_code);
        } break;