Error in initializing ST-LINK device. Reason: No device found on target.(Stm32H755)

[remoter]

Recently, I got some projects from my professor and tried to solve that with my Nucleo-H755 Board.

I found that the way How to debug this MCU, Stm32H755 is pretty different with other st mcu, so i followed this video to set the debugging environment.

https://www.youtube.com/watch?v=jI1k6p-fduE

After applying some settings, I checked that my board got a problem.

I couldn't connect to my board anymore(Cubeide- Debugging Mode or Cube programmer connecting) but still can check the voltage of st-link and volume of memory Storage.

I would really appreciate it if you could give me a suggestion to solve this problem.

Thank you.

[TDK · Accepted solution]

> After applying some settings

What settings were those? Did you change SMPS/LDO settings? Recovery instructions are here:

https://community.st.com/t5/stm32-mcus/how-to-unbrick-an-stm32h7-after-setting-the-wrong-power-mode/ta-p/49691

If it was something else, you can generally recover by holding BOOT0 high during reset.

[remoter]

I just solve the problem after applying your advice. Thank you for your help!

[PG.1]

Hello!

I have a similar problem. I have a few boards using F767. I'm using stlink V3 with the half-pitch connector,

only the central 10 pins (i.e. pins 3 to 12). It used to work perfectly. Last time I compiled program for these

boards was (possibly) 1 ~ 2 years ago.

-> Did something change in latest firmware of STLink V3, that would prevent it to connect?

Just in case, I have setup BOOT0 high, and it doesn't change. Still that "no device found on target".

By the way, what do you mean by holding BOOT0 high during reset? Do you mean that it should

be high when the reset signal goes low, and then it should be low for the rest of the boot?

Thanks

[TDK]

Nothing has changed in 2 years that would prevent st-link v3 from working.

Holding BOOT0 high during reset means do the following in order:

• Pull NRST low
• Hold BOOT0 high
• Release NRST (it will be pulled up internally)
• Release BOOT0 (value only matters immediately after reset)

If you're still having issues, perhaps create a new post with your specific details. Ensure the chip is powered and that STM32CubeProgrammer correctly reports a valid voltage.