Use NUCLEO-H745ZI-Q on-board STLINK-V3 as external debugger

[DTomi.1]

Greetings,

I'm trying to use the STLINK-V3 debugger and programmer which is included on the NUCLEO-H745ZI-Q dev board to connect to external STM32. I have read https://community.st.com/s/question/0D53W00000OmiV6SAJ/nucleoh732zg-has-strange-new-stlink-part and that seems to be possible, someone suggested cutting SWDIO and SWCLK traces, but my board has the capability to completely disable the power to the STM32H745ZI by means of disconnecting the JP4 jumper which connects VDD to VDD_MCU which powers it. I have connected my wires to the CN5 connector (MIPI10 on STDC14 footprint) I have confirmed that I'm getting SWCLK and SWDIO signals from the STLINK-V3 but I'm constantly getting "Error: No STM32 target found!" in STM32CubeProgrammer.

The FW version of ST-LINK is V3J7M2.

Can anyone help me with this?

BR

Domagoj

[Imen.D]

​Hello @Domagoj Tomić​ ,

Do you have set mode to "Under Reset" ?

Maybe you have the same issue as in this post.

Imen

[DTomi.1]

No I didn't, seems like new Nucleo boards can't be used as external debuggers, which is a shame.

[Uwe Bonnes]

I think, you can only connect an external debugger not use as an external debugger. This is different from StlinkV2 on other Disco/Nucleo boards.