How to use the watchdog when DFU

[roy756456625]

Hi

I opened the Watchdog in the user application,and do nothing in the bootloader.Then when I use DFU,the CPU reset appears.How can I to deal with it?

And when I upgrade willful termination APP(nRF Toolbox),the CPU(nRF52832)is down,and can't work.Do you have any suggestions on how to solve this fault tolerance?

Thank you!

[bjorn-spockeli]

You'll have to "feed" the watchdog in the bootloader, i.e. call

NRF_WDT->RR[0] = 0x6E524635UL;

in order to prevent the watchdog timer from timing out and resetting the chip.

-Bjørn

[bjorn-spockeli]

@nikula (Jarmo): Are you using the nRF51 or nRF52? Are you using the legacy or the secure bootloader? How long is the WDT interval? If its the latter, then I would put it in the nrf_dfu_req_handler_on_req() function in dfu_req_handling.c, see this answer.

You should be able to configure the WDT after a reset according to the documentation, see this link.

When the device starts running again, after a reset, or waking up from OFF mode, the watchdog configuration registers will be available for configuration again.