Resume from Stop & Standby mode

[danc]

Posted on December 09, 2008 at 18:52

Resume from Stop & Standby mode

[danc]

Posted on May 17, 2011 at 12:55

I'm seeing some odd behavior when I resume from a Stop or Standby condition. Before issuing the Stop command the 3.3V rail is consuming about 50mA and after the Stop is issued the current drops to about 10mA on this rail (this is what I would expect). I issue a rising edge on PA[0] WKUP pin to resume normal operation and I would expect the current consumption to go back to about 50mA but it only goes up to 20mA?? I've configured a timer to trigger a flashing LED and when I come out of Stop mode I also notice that the LED is flashing at a much lower duty cycle. It seems like something is slowing down the main clock after I resume from Stop. Is there something I'm missing?

Regards, Dan

[relaxe]

Posted on May 17, 2011 at 12:55

Section 4.3.4 of RM0008:

''Exiting Stop mode: When exiting Stop mode by issuing an interrupt or a wakeup event, the HSI RC oscillator is selected as system clock.'' you have to re-select/change the clock source upon wakeup for normal operation. You probably have a ''RCC_Configuration'' function if you just drew your application based on the various ST exemples. Calling it on the wake-up event would bring back your original settings. -Relaxe

[danc]

Posted on May 17, 2011 at 12:55

That was it exactly. Thanks for the quick reply.

Dan