sd_app_evt_wait();

Question

Hi 
 I'm using sd_app_evt_wait(); to go into low_power mode.
For some reason it comes back immediately, but I can't figure out why. 
 If I call it a second time it stays asleep as it should.
Is there any way to see why sd_app_evt_wait(); comes back again? 
 I have tried to put breakpoints in all my handlers, but no hit there.
Adding a delay before the first call didn't help either. 
 Best regards
/Håkan

John · Accepted Answer

This note in the documentation for sd_app_evt_wait(); may explain what you are seeing: "If an application interrupt has happened since the last time sd_app_evt_wait was called this function will return immediately and not go to sleep. This is to avoid race conditions that can occur when a flag is updated in the interrupt handler and processed in the main loop." 
 The only other alternative is you have a disabled interrupt with its pending flag set. That seems less likely since you do not mention clearing any pending interrupt flags.

sd_app_evt_wait();

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