Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

Martin Lesund — Thu, 07 Jun 2018 12:54:27 GMT

According to Source, the 0x3D HCI error is #define HCI_ERR_CONN_TOUT_DUE_TO_MIC_FAILURE 0x3D line 511

It is clearly a bug in Moto since it works on other phones.

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

jmuralinux — Wed, 06 Jun 2018 15:58:36 GMT

yes.. We have handled errors as required. In this case, it throws 0x3D error in the DISCONNECTED event and disconnects immediately. So we restart the advertising and it connects again and goes in this loop. After 5 seconds or so, it eventually succeeds but intermittently.

When it connects successfully, it keeps doing connection param negotiation every few seconds as well as below changing the params often.

BLE_GAP_EVT_CONN_PARAM_UPDATE
Connection Param Negotiation
Pref Min Interval 16 Pref Max Interval 60 Recv Max Interval 6 Recv Min Interval 6

BLE_GAP_EVT_CONN_PARAM_UPDATE
Connection Param Negotiation
Pref Min Interval 16 Pref Max Interval 60 Recv Max Interval 60 Recv Min Interval 60

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

Martin Lesund — Wed, 06 Jun 2018 08:53:03 GMT

- From what function do you get the error 0x3D?

- Do you have an error handler in your project?

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

jmuralinux — Tue, 05 Jun 2018 01:56:36 GMT

Thanks. sd_ble_gap_ppcp_set is called during power up setting up BLE. sd_ble_gap_conn_param_update requires a connection handle. So I called this once I got the CONNECTED event is received before doing MTU negotiation and it connects and disconnects immediately with error 0x3D. The error on the nRFTools app still reports the original error and keeps connecting and disconnecting in the background whereas the app shows status as connected even though logs confirm the connection/disconnection.

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

Martin Lesund — Thu, 31 May 2018 08:33:23 GMT

If you are not using our SDK:

- Then you have to run a sd_ble_gap_conn_param_update() to trigger a parameter update from the peripheral. If you have used sd_ble_gap_ppcp_set() before that, then you can use NULL for *p_conn_params for sd_ble_gap_conn_param_update().

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

jmuralinux — Fri, 25 May 2018 05:03:19 GMT

We are using s140_nrf52_6.0.0 Soft device and not using SDK.

I read the thread earlier but do not really understand what handle is to be set. We are setting the start_on_notify_cccd_handle to BLE_GATT_HANDLE_INVALID and calling the sd_ble_gap_ppcp_get. Any inputs on which handle to be used here?

Thanks!

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

Martin Lesund — Thu, 24 May 2018 14:19:11 GMT

- What SDK version and Softdevice version are you using?

- Have you seen this thread? (It may be of help)

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

jmuralinux — Wed, 23 May 2018 16:42:02 GMT

The issue that I noticed is with both nRFConnect and nRFtoolbox apps. i will try the device cache option and update.

Our solution with this product is targeted for a wide audience and we do not control what phones the customers can use and would like to understand if this is a limitation on Moto E4 itself or Android or Nordic (soft device). If there is a work around possible, we would like to try that as well. Our own app and the nRF apps work fine with quite few other phones that we tested with (as mentioned in my OP).

RE: Moto E4 fails to connect with nRFConnect app itself (Error 0x85 - GATT ERROR)

Martin Lesund — Wed, 23 May 2018 12:21:07 GMT

Hi Jmuralinux,

Does it work better with nRF Connect?

Seems like there is an issue with the Moto E4. I have two proposals to you:

1. Try to refresh the device cache (use nRF Connect to check if it works, then try it in the app)

2. Change the phone?