STM32 Sleep

[SARTHAK KELAPURE]

Posted on January 29, 2018 at 13:02

What is the best way to put STM32L0 micro-controllers to sleep for limited time duration(preferably using RTC)?

#stm32l0 #stm32-sleep

[Andrew Neil]

Posted on January 29, 2018 at 13:14

There is no such thing as 'best' - it all depends on your particular requirements.

It is a tradeoff between

• current consumption while in sleep;
• functionality while in sleep;
• available wakeup triggers;
• time taken to 'wake up' from sleep;
• amount of reconfiguration required to enter & exit sleep;
• etc...

[SARTHAK KELAPURE]

Posted on January 29, 2018 at 13:18

Well, in that case, I would like to wake the controller on an RTC timeout and would like to have low power consumption(not the least, functionality is priority). Is this possible?

[Andrew Neil]

Posted on January 29, 2018 at 13:41

So have you looked at the Datasheet and Reference Manual - they list & describe the available 'sleep' modes ...

The STM32L0x2 Reference Manual, at least, has code examples at the end ...

[Tesla DeLorean]

Posted on January 29, 2018 at 18:08

Pretty sure the LRWAN implementation is illustrative of the RTC being used as the primary timebase, placing the device into SLEEP state(s)

[Andrew Neil]

Posted on January 29, 2018 at 18:19

Yes, it is - though rather a lot to wade through just for an example of SLEEP ... !!

:(

[Tesla DeLorean]

Posted on January 29, 2018 at 18:21

But the mechanics are at least fully explored. And the OP was using the LoRa L0 code previously.

[Andrew Neil]

Posted on January 29, 2018 at 18:37

Oh yes - so he did: 

https://community.st.com/community/stm32-community/blog/2017/04/05/lora-discovery-kit?commentID=4845&sharpcomment-4845

 

[SARTHAK KELAPURE]

Posted on January 29, 2018 at 18:46

Even though my recent work has been on LoRa discovery board and on LoRa, I just wanted to know best possible way for STM32 controllers to go to sleep and wakeup. Also, right now I am still on LoRa stack and wish to best utilize the sleep options available.

[Andrew Neil]

Posted on January 29, 2018 at 18:54

Again, 'best' is meaningless - unless accompanied by a specific set of criteria by which to judge it.

If there was just one single 'best' option - why would the chip provide any others?