wfi instruction stops systick timer

RE: wfi instruction stops systick timer

Håkon Alseth — Wed, 31 Aug 2022 07:44:56 GMT

systick behavior is implementation specific, ie. it is up to the vendor how its clocked. Systick only runs when the CPU is running in nRF52/nRF53 series devices.

We strongly recommend that you use the RTC instead, as also recommended in the thread that you linked to, for better energy efficiency (ie. lower power in sleep).

Kind regards,

Håkon

RE: wfi instruction stops systick timer

Bas van den Berg — Wed, 31 Aug 2022 07:12:41 GMT

I have the same thing (post NRF5340 WFI causes Systick to stop? ). When reading back the SYST_CSR register it always reverts back to 7 (bit 2 is set). Bit 2 is the clock source (1=processor, 0=external).

RE: wfi instruction stops systick timer

Wojciech Puchar — Fri, 25 Jun 2021 09:01:33 GMT

Update: Everything works as expected if i use TIMER0 to generate interrupts every 1ms instead of systick. Including WFI.

So for now it's fine me, i will not need more than 4 other timers in my program. But still i would like to know why it doesn't work with systick