CRC error in bootloader when watchdog is enabled

[SirenB]

Hello,

I encountered a crc check error when update application via bootloader. The SDK version is 12.2.0. I found that this error is related to watchdog.

In the beginning, I add watchdog initialization code in application and add watchdog feed action in bootloader wait_for_event function, but the bootloader will reset, seems that feed action doesn't take effect.

and then I try to add watchdog initialization code in to bootloader too, the watchdog feed action in bootloader is totally same as before. This time, bootloader will not reset when doing firmware upgrading. But when firmware transfer finished, I got a CRC error, firmware CRC validation fail.

The weird thing is that when I erase all the chip and then program softdevice and bootloader but without application, the CRC error is disappear. The crc error just appear when I try to do upgrading when application was run.

I found someone seems has same issue with me: devzone.nordicsemi.com/.../

But I have found the root cause in this page, when the CRC error happen.
Feed watchdog just in wait_for_event function is not enough?

Best Regards Jerry

[SirenB]

I feed the watchdog in bootloader with function nrf_drv_wdt_feed

[bjorn-spockeli]

Hi SirenB,

It would appear that you might have to feed the WDT in nrf_dfu_app_continue() in nrf_dfu_utils.c as explained in this answer.

[SirenB]

Thanks. It works.

[bjorn-spockeli]

Happy to help :) I would appreciate if you could mark the answer as accepted/correct by clicking the checkmark in the grey circle to the left of the answer.

[Guillaume LS]

You will face the same watchdog issue if you try to update the SoftDevice. I think the same fix has to be applied also in the nrf_dfu_sd_continue_impl() function.