BLE connection issue on Colibri IMX6ULL

Hi, I have Colibri imx6ull SOM with Colibri Evaluation board and trying to use internal Wi-Fi/Bluetooth module to connect with board over BLE. I have connected two Unictron AA 222 antenas to Wi-Fi/Bluetooth module and using build Yocto dunfell-5.x.y image. I have faced with BLE connection issue, I tried to connect to board using nRFConnect utility on my mobile phone, but BLE connection constantly disconnects after few seconds. btmon utility shows the disconnect reason: Connection timeout.
2520-disconnect-reason.png

Also I have checked this issue on pre-built Toradex images with 3.0.4 and 5.0.1 versions, but this images also have the same issue with my Yocto image. How can I resolve this issue?

Hi @askripko and Welcome to the Toradex Community!!!

Could you flash the latest 5.1 release and follow these instructions to do a Bluetooth connection and report the errors in text format?

Thanks and best regards,
Jaski

@jaski.tx thank you for your answer. I have tested BLE connection on Toradex 5.1.0 release, it has the same issue.

> HCI Event: Disconnect Complete (0x05) plen 4                                                                                                                                               #35 [hci0] 123.892220
        Status: Success (0x00)
        Handle: 128
        Reason: Connection Timeout (0x08)
@ MGMT Event: Device Disconnected (0x000c) plen 8                                                                                                                                       {0x0001} [hci0] 123.892356
        LE Address: C8:F7:33:DB:5A:0F (Intel Corporate)
        Reason: Connection timeout (0x01)

But BLE works good (no disconnections occur) after I establish Bluetooth Classic connection as described in instruction above. But in my case I need only BLE connection.

Hi @askripko

Thanks for your Input.

But BLE works good (no disconnections occur) after I establish Bluetooth Classic connection as described in instruction above. But in my case I need only BLE connection.

What do you differently in your only BLE Connection case?

Best regards,
Jaski

@jaski.tx In BLE connection case I enable advertising and low energy support, using btmgmt utility on the device. After that I trying to connect from Mobile Phone using nRFConnect utility and after few seconds it disconnects.

@jaski.tx I can share with you simple shell script that I use to enable BLE on the device.
Firstable you need to unblock bluetooth device by next rfkill command:
rfkill unblock bluetooth
After that you can runenable_ble.sh script and connect to device using nRF Connect utility on Mobile device or something like that. enable_ble.sh using btmgmt tool to setup Low Energy support on the device, but Toradex image doesn’t have this tool in default. I also can share this utility with you.
BLE tools

Hi @askripko

I tested this on my side with nRF connect on Galaxy J5 and i didn’t see any automatic disconnection. Are you using two antennas on your side? If yes, which ones?

Best regards,
Jaski

Hi @jaski.tx. Yes, I am using two Unictron AA 222 antenas. I have this issue on three boards.

Thanks. Which mobile phone are you using?

I have this issue on three boards.

Three out of how many boards? Did you install the same image on these devices?
Which carrier board are you using?

I have only three Colibri Evaluation V3.2B boards. Yes, I tested with the same image on these devices.

Which mobile phone are you using?

I have tested on different phones, Nokia 6.1 Plus, IPhone XR.

Hi @askripko

We tested also on Pocophone and we still don’t see any issue. We will continue to test with some other phones to reproduce the issue.

Best regards,
Jaski

Hi @askripko

We also made Tests with some other phones as IPhone and we didn’t see any issues.
Could you share the dmesg.log when this disconnection happens?

Best regards,
Jaski

Hi @jaski.tx
I don’t see any specific messages in dmesg log when the disconnection happens, the dmesg log doesn’t change during disconnection. I have connected the USB Bluetooth dongle and it works well with BLE connection, but I would like to use builtin Bluetooth/WiFi module. Can it be the specific issue with my modules?

Hi @askripko

I don’t think that your modules are damaged. Its more the whole setup. If you wish, you could file up a RMA and we can make the tests with one specific module on our side.

Best regards,
Jaski