Debug Mode & Voltage Scaling

[MVeen.1]

I'm using a STM32L151RBT6 and trying to debug with a STLink V3.

The debugger loses connection when I encounter the line:

PWR_VoltageScalingConfig(PWR_VoltageScaling_Range3);

 

Specifically, when it changes the PWR-CR Bits 12:11 (VOS). I have no issue changing it to Range 1 or 2, but 3 results in this message:

"ST-LINK device status: Failed to get status, Target not responding, retrying... 19"

 

Any help would be greatly appreciated!

STM32L100xx, STM32L151xx, STM32L152xx and STM32L162xx advanced Arm<Sup>®</Sup>-based 32-bit MCUs - Reference manual

[Amel NASRI]

Hi @MVeen.1 ,

Please make sure to be aligned with the maximum CPU frequency allowed for Range 3 (as explained in this table):

-Amel

[danirpg]

This happens to me as well in STM32H573RIT but when setting the VOS to 2 or 1 or 0.

[Tesla DeLorean]

Seems unrelated. You could perhaps drop the connection speed, to 500 KHz or 1 MHz

Perhaps open as a new question, or attach schematic of custom board to better understand your situation.

Something that's just started to fail?

[danirpg]

I found the problem was on a bad SWD cable, but interstingly it only crashes when changing the voltage scaling.