Pausing RTC when device goes to sleep (WFE)

[juliantbrown]

I'm looking into using the RTC on the nRF52840 as a Watchdog timer. The reasons being the increased flexibility that this would provide for saving context information prior to reboot and also to shave power consumption by a few µA.

The issue is that when the nRF52 drops into its low-power mode via __WFE, the calls to feed the watchdog (resetting the RTC) no longer occur, but the RTC continues. Is there a way to pause the RTC when the nRF52 enters the WFE state and start it back up when the Nordic wakes? 

[Stian Røed Hafskjold]

Hi, you can stop and start the RTC with the TASKS_STOP and TASKS_START registers: https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/rtc.html?cp=3_1_0_24_9#topic

You can try to add the STOP before WFE and START right after.