Skip to main content
Associate II
August 14, 2026
Solved

STM32H562: Immediate standby mode makes µP inaccessible

  • August 14, 2026
  • 4 replies
  • 22 views

Hello,

 

I want to measure the power consumption of the rest of my circuit. For that, I’m putting the STM32H562 immediately to sleep. I generate a cube project and put the following in main():

int main(void)
{
HAL_PWR_EnterSTANDBYMode();
}

 

After flashing, the current consumption suggests that it is not running, but I’m not sure. I switch the power off and on again, the current drops by 2.2mA down to 0.5mA (including the rest of the circuit).

But now, it is not possible to connect to the processor with the cube programmer. I have to do a discover first, before being able to connect to it again. MY expectation would have been that I’m directly able to flash again.

My questions are now: Why does entering the standby (or stop) mode locks the access to the device. Is this a bug or a feature? Is is documented somewhere?

 

Best regards,

Peter

 

Best answer by peter7

Hello,

 

thanks for the replies. I already tried NORMAL/HOTPLUG/UNDER RESET before without success.

But POWER DOWN is working!

 

ST-Link V2, custom board.

 

 

4 replies

AScha.3
Super User
August 14, 2026

Hi,

board ?  

st-link V..?

  • look in CubeProgrammer, connect : under reset , hardware reset; + low power.
  • try power down , under reset...etc.

 

 

ok then ?

 

 

If you feel a post has answered your question, please click on " Best Answer ".
Andrew Neil
Super User
August 14, 2026

You’ll need to connect under reset.

 

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.
peter7AuthorBest answer
Associate II
August 14, 2026

Hello,

 

thanks for the replies. I already tried NORMAL/HOTPLUG/UNDER RESET before without success.

But POWER DOWN is working!

 

ST-Link V2, custom board.

 

 

Andrew Neil
Super User
August 14, 2026

If that’s resolved the issue, please mark the solution on the post which provided the answer - not this one! 

Otherwise:

 

ST-Link V2

A real one?

 

custom board

please show schematics

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.