STM32F103C8: wakeup from standby using RTC

turboscrew · ‎2017-01-26

Posted on January 26, 2017 at 14:53

I've been trying to get the device to wake up from standby using RTC alarm, but it doesn't seem to wake up.

I think it goes to standby, because the debugger loses connection - the interface seems to get unpowered.

How do you set up RTC to wake up the device without CMSIS-stuff?

(I'm not using CMSIS-stuff, because I'm trying to learn the HW, not the libraries.)

I've connected the +3.3V also to Vbatt just in case...

The RTC runs using LSE, and it seems to set the alarm flag as wanted, when the standby is not entered.

(The WFI/WFE is replaced by RTC alarm flag polling loop.)

What are the steps needed to configure the system (without CMSIS-stuff) to be waken up from standby by the RTC alarm?

#rtc-alarm #standby #stm32f103

turboscrew · ‎2017-01-26

Posted on January 26, 2017 at 22:11

Forget it. The problem seemed to be that I set the ALRIE-bit in RTC_CRH.

When I removed that, the wakeup started working fine.

The mask probably re-routes the ALRF to some wakeup module instead of nowhere when

the device is in standby and ALRIE is clear?