NUCLEO-H755ZI: ST-LINK detected but “No STM32 target found / Unable to get core ID”

[Renee]

Hello STM32 Community,

I am a newbie and facing an issue with my NUCLEO-STM32H755ZI board.

I am unable to connect to the STM32H755 target using STM32CubeProgrammer, even though the ST-LINK appears to be working correctly,

Hardware

• Board: NUCLEO-STM32H755ZI

• Debugger: On-board ST-LINK

• USB connection: CN1 (USB-A to Micro-B).

  Software

• STM32CubeProgrammer: v2.21.0

• OS: Windows

• Connection mode: ST-LINK / SWD

• Observed Behavior

  • ST-LINK is detected correctly by Windows

  • ST-LINK Virtual COM Port is visible in Device Manager

  • Target voltage ~3.27 V is shown in Cube programmer.

     

  • Green power LED (LD3) is

  • Red ST-LINK LED is blinking
  • Error: No STM32 target found!
    Unable to get core ID
    If your product embeds Debug Authentication,
    please perform a discovery using Debug Authentication
    

[AScha.3]

Hi,

Did it work before? Did you flash anything?

Try connecting with setting: hardware reset.

Did you change/set the power supply setting?

Maybe then need start the bootloader by setting the boot0 high and then power up with dfu mode to recover to a working state.

[Andrew Neil]

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@AScha.3 wrote:

Did you change/set the power supply setting?

---

@Renee - see: How to unbrick an STM32H7 after setting the wrong power mode.

Also, for general debugger connection issues:

How to solve connection errors when connecting and programming the STM32 target board.

How to solve debugger connection issues.