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KL82Z - STOP mode vs tickless idle

Question asked by nickbedbury on Apr 9, 2019
Latest reply on Apr 19, 2019 by nickbedbury

Setup

I'm trying to get a KL82Z to operate in RUN mode when necessary (when tasks need to execute), otherwise STOP mode to save power. 

  • My project employs freeRTOS and Processor Expert (PE) via Kinetis Design Studio IDE
  • I'm using KSDK 1.3.0
  • I enabled tickless idle as well as the idle hook

 

Questions

1) Does configuring PE as follows enable both RUN and STOP mode?  Or do I need an explicit configuration for STOP as well?

 

2) I'm aware of the `power_manager_rtos_demo` from KSDK and have seen really low power usage in STOP mode.  In the demo, there are calls to `POWER_SYS_SetMode()` when a user enters a selection.  With tickless idle and/or Processor Expert, can I expect power mode switches to happen automatically?  Or will I need to add such calls, in `vApplicationIdleHook()` for instance?

 

3) More generally, what is the difference between STOP and the tickless idle state?  It seems like STOP is lower power, but tickless idle is easier to use in freeRTOS.

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