FreeRTOS sleep optimization from main task

RE: FreeRTOS sleep optimization from main task

Susheel Nuguru — Fri, 06 Dec 2019 08:59:04 GMT

[quote user="bfriedk1"]If we enable the SoftDevice when our application launches, can we still set the bit in the SCB to enable System ON sleep and achieve the same sleep management result after the SoftDevice is enabled?[/quote]

Yes, you can enable it even with the softdevice enabled.

RE: FreeRTOS sleep optimization from main task

bfriedk1 — Fri, 06 Dec 2019 01:44:42 GMT

Susheel -

Great! Thank you for the additional details. One more small follow-up question... If we enable the SoftDevice when our application launches, can we still set the bit in the SCB to enable System ON sleep and achieve the same sleep management result after the SoftDevice is enabled?

Thanks,

Brian

RE: FreeRTOS sleep optimization from main task

Susheel Nuguru — Thu, 05 Dec 2019 07:37:39 GMT

Hi Brian,

Your understanding is correct. There should not be any other sleep management in the tickless idle apart from the one in vPortSuppressTicksAndSleep. The call to xQueueReceive will block the calling task if there are no messages in the queue and hence will call the scheduler. Which means that this task is yielding correctly in this scenario and if there are no other tasks to run apart from the idle task, then vPortSuppressTicksAndSleep will be called and the system will go to sleep mode. You do not need to worry about the softdevice wakeup routines as sd_app_evt_wait call will only wake the application if it is application specific event.