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Associate III
February 6, 2025
Solved

How to wake up from standby mode?

  • February 6, 2025
  • 9 replies
  • 3774 views

I am using an stm32c011 MCU and want to put my device into standby mode and then periodically wake it up (every 30s or so).

I have seen guides which use the RTC to do that, but cube mx doesn't show me a WakeUp option on my RTC

DavidL__0-1738849020205.png

Am I missing something or how am I supposed to continue from here?

This topic has been closed for replies.
Best answer by KnarfB

On a STM32C0, RTC cannot wakeup from standby mode, see ref.man Table 19. "Device resources enabled in different operating modes"

But, for short intervals like 30s, you may use the IWDG for that.

hth

KnarfB

9 replies

Andrew Neil
Super User
February 6, 2025

The Data Sheet and/or Reference Manual will list all the available ways to exit the various low-power modes - so look there to see what RTC feature(s) are available to wake-up...

An Alarm, perhaps ... ?

 

PS:

Datasheet says RTC is turned off in Standby Mode - so not a wakeup option:

AndrewNeil_0-1738851531179.png

 

So your options are:

  • external reset (NRST pin)
  • IWDG reset
  • wake-up event (WKUP pin, configurable rising or falling edge)

 

A complex system that works is invariably found to have evolved from a simple system that worked.A complex system designed from scratch never works and cannot be patched up to make it work.
KnarfB
KnarfBBest answer
Super User
February 6, 2025

On a STM32C0, RTC cannot wakeup from standby mode, see ref.man Table 19. "Device resources enabled in different operating modes"

But, for short intervals like 30s, you may use the IWDG for that.

hth

KnarfB

DavidL_Author
Associate III
February 6, 2025

Thanks, I'll try that.

ST Employee
February 6, 2025

Hello @DavidL_, 

As already said by everyone, always check this table in your product RM: 

 

SarraS_0-1738851914325.png

"-" = resource not available / without wake-up capability (grayed-out columns)

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.
DavidL_Author
Associate III
February 6, 2025

Thank you, I was looking in the datasheet which was the wrong place :)

Andrew Neil
Super User
February 6, 2025

@DavidL_ wrote:

I was looking in the datasheet which was the wrong place :)


As shown, the information is also in the datasheet!

A complex system that works is invariably found to have evolved from a simple system that worked.A complex system designed from scratch never works and cannot be patched up to make it work.