RE: RTC Registers state after soft reset and OTA.

Mukesh Kumar — Thu, 23 Apr 2020 14:46:31 GMT

Hi Edvin,

I really appreciate your quick and detailed response.

Your answer was really helpful and it cleared all my doubts.

Thanks a lot !!

RE: RTC Registers state after soft reset and OTA.

Edvin — Thu, 23 Apr 2020 12:19:23 GMT

Hello,

The RTC is a peripheral, and unfortunately, all the peripherals are reset on all reset reasons, even soft resets, as you can see here. This means that you will reset the counter whenever you reset the nRF52832. (OTA triggers several soft resets).

If you want to retain the value, you can try to write it to RAM, which is never actively reset (but may reset if the nRF reset was caused by a power out or brown out). But remember that before you start up again, the RTC will not be running, so you may loose some time every time you reset. You also need to consider how often you want to copy the counter register to RAM. every minute? Every second? More often?

The last option is to save the time in flash, which requires you to do flash operation every time you want to save the time. This will of course cost some power, and it is fairly slow (compared to ram, or the register itself). Perhaps an external battery driven RTC (Real time clock), and not the Real time counter that is present on the nRF is what you need, in order to keep track of time between resets and power outs.

BR,

Edvin