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Associate
July 7, 2025
Question

STM32H757 dual core debugging issue

  • July 7, 2025
  • 2 replies
  • 342 views

The last couple of months I have been developing on an STM32H757I-EVAL board. Programming and debugging (multi-core) works reasonably well; although sometimes I need to re-power the board.

During the last weeks, we transitioned from the EVAL board to the actual PCB design. Since then I have a lot of issues with debugging of the board.

I use the ST-LINKV2 debugger in combination with STM32CubeIDE 1.18.0.

Most of the times, the ST-LINK GDB server refuses to connect with the following error:

Target connection mode: Under reset

Target connection failed

Target no device found

Error in initializing ST-LINK device.

Reason: No device found on target.

Playing around with the setting shows that the ST-LINK GDB server does not connect when having the '--halt' option specified (to halt both cores). When I omit this flag, the GDB server is able to connect to the target.

I need to re-power the board to get it working again (for a couple of tries, after that it stops again)

Are there any known issues, or do you have any suggestions how I can solve the issue?

2 replies

Peter BENSCH
Technical Moderator
July 7, 2025

Welcome @MiNe, to the community!

In order to analyse your problem more precisely, it would be useful if you could add photos of your your ST-LINK/V2 here, back and front please.

Regards
/Peter

MiNeAuthor
Associate
July 7, 2025

MiNe_0-1751870992576.png

I am getting this error while I am debugging both cores simultaneously.