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Low Power Wake-Up

Question asked by burgeh on Oct 23, 2018
Latest reply on Nov 11, 2018 by Jing Pan

Greetings,

 

I am currently using the MK22FN256LVH12 microcontroller with KDS v3.2 and Processor Expert.

 

I am looking to put the controller in a lower power mode. I currently am able to put it in a STOP mode in which it will wake up from a LPTMR from the code below.

 

//setup timer

LPTMR_PDD_WriteCompareReg(LPTMR0_DEVICE, 59);
LPTMR0_CSR &= ~1; //disable timer
LPTMR_PDD_EnableInterrupt(LPTMR0_DEVICE);

 

Later in the code I enable it and sleep. This works for DOM_SLEEP which sets it in STOP mode.

 

I read in the datasheet that when in VLLS1 or VLLSx that it can only be awaken by Wakeup Reset. Can this only done by hardware? There is a function I use which hard resets the controller by firmware. However, I doesnt seem like my LPTMR event is being achieved in this mode (I turn an LED on in the event where the timer overflows, and it never turns on).

 

Thoughts?

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