Zephyr SMP Server sample does not work on nRF52840 DK

[V1incentC]

Hello,

I am using the Zephyr SMP Server sample to update the firmware over BLE on a custom board with the nRF52840 and a nRF52840 DK. I followed the instructions in the documentation to configure and build the sample, and I used the nRF Connect app on my smartphone to connect to the device and upload the firmware image.

The problem is that the SMP Server sample works fine on my custom board, but not on the nRF52840 DK. When I try to update the firmware on the DK, I get a [McuMgr] Error (0x1): GATT INVALID HANDLE message in the app.

Can anyone please help me figure out what is causing this issue and how to fix it? Is there something different between the custom board and the DK that I need to consider? Is there a bug in the Zephyr SMP Server sample or in the nRF Connect app?

Thank you in advance for your assistance.

[V1incentC]

Hi Andreas,

Thank you for your detailed response. I followed the steps you provided and managed to perform a firmware update successfully when I switched to a different phone (Pocophone F1).

However, I encountered an error in the RTT log related to LittleFS. Here’s the log for your reference:

The error message “Corrupted dir pair at {0x0, 0x1}” appeared and it seems that LittleFS couldn’t mount and had to format. I’m wondering if this is something I should be concerned about

Kind regards,
Vincent

[AHaug]

Glad to hear that you resolved the issue with the guide and a different phone

AFAIK the warnings and errors highlighted are caused by LFS needs to be initialized, which is usually handled sometime right after restarting the firmware

In my end the warning and error is gone after restarting the firmware both for the initial firmware running, and the updated firmware after dfu, i.e: Flash, reboot dk and see the warnings disappear, perform dfu -> reboot DK and see warnings disappear

Does the warnings persists after you reboot the dk after performing DFU?

Kind regards,
Andreas

[V1incentC]

The warnings are gone after the reboot.
Thanks a lot for your help!