AnsweredAssumed Answered

Wait mode doesn't seem to work

Question asked by Ahlan Marriott on Aug 15, 2018
Latest reply on Sep 12, 2018 by igorpadykov

I am using an MCIMXRT1052 processor and seem to be having a problem understanding the wait mode.

I use a GPT timer and the Wdog3 and have configured both of these to be disabled in wait mode.

I am therefore surprised that the GPT timer still counts whilst the processor is executing the WFI instruction.

Moreover the watchdog can go off whilst processing the WFI instruction.

My understanding is that executing the WFI instruction places the processor into Idle mode until the next interrupt.

And that if the least significant 2 bits of CLPCR are 01 then Idle will transfer to Wait mode.
CLPCR defaults to 79H - I have checked this.
So why don't we go into WAIT mode?

Or if we do why does the GPT and Watchdog still count?

Do I have to configure low power gating (CG12 in CCM_CCGR0)?

I tried this but it didn't seem to help.

 

I guess I am misunderstanding a concept or not configuring the processor correctly.

So any clues, suggestions & ideas are all very welcome.

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