NRF52840 issue with IOS 5.0 Devices

[LukeC]

Okay, this is a fairly involved issue, so I will try to simplify as best as I can.

In short, my new Ipad Mini 5 cannot connect to an NRF52840 running the NUS peripheral ( SDK15.3, SD-140-6.1.1). The Ipad Mini 5 can successfully connect to a nrf52832 running the NUS peripheral (SDK15.3, SD-132-6.1.1).

My older IOS devices can connect to both no problem.

I can see that the GAP layer connects from the RTT with the Ipad Mini 5 and the 52840, but the Ipad Mini 5 never hits the didConnect peripheral callback and thus no GATT services discovery is performed.

I see this problem both on my custom IOS apps and the Nordic NRFConnect App on the app store.

Device	Chip	SoftDevice	SDK	Can Connect
Ipad Mini 5	52832	6.1.1	15.3	YES
Ipad Mini 5	52840	6.1.1	15.3	NO
Ipad Mini 4 and Older IOS devices	52832	6.1.1	15.3	YES
Ipad Mini 4 and Older IOS devices	52840	6.1.1	15.3	YES

My only guess is that there is some BLE setting on the nrf52840 that is telling the newer 5.0 devices something incorrect ( 2.0 mbps? Long-range?).

Any other ideas what could be going on here?  Can someone test the nrf52840 example with a newer IOS 5.0 device?

This problem seems to be the same as what others are reporting with the nRF-Connect App - https://github.com/NordicSemiconductor/IOS-nRF-Connect/issues/50

[Mttrinh]

Hi,

I'm not sure what is causing the issue. I try testing this over here with a newer device with BLE 5.0. Do you use an unmodified version of the UART example from the SDK?

[LukeC]

I figured out the problem.  I was porting a project from an old S132 project and this GAP request event was not being handled:

        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;