Debugging with OpenOCD and STLink v3 in VSCode

[BobbyBeta]

I started a new job where everyone is using VSCode so I'm attempting to be a good citizen and use it to. Before this I used STM32CubeIDE. Unfortunately nobody is here to help me today and I'm hoping to work over the holidays.

I can build in VSCode for an STM32F423CHU6 but I can't debug it. I am using an ST-Link v/3. When I try to debug I get the message "OpenOCD: GDB Server Quit Unexpectedly. See gdb-server output in TERMINAL tab for more details." 

When I go to the terminal I see:

Open On-Chip Debugger 0.11.0 (2021-03-07-12:52)
Licensed under GNU GPL v2
For bug reports, read
        http://openocd.org/doc/doxygen/bugs.html
CDLiveWatchSetup
Info : auto-selecting first available session transport "hla_swd". To override use 'transport select <transport>'.
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
Info : Listening on port 50001 for tcl connections
Info : Listening on port 50002 for telnet connections
Info : clock speed 2000 kHz
Error: open failed


[2023-11-22T17:34:49.660Z] SERVER CONSOLE DEBUG: onBackendConnect: gdb-server session closed
GDB server session ended. This terminal will be reused, waiting for next session to start...

I see the clock speed of 2000 kHz which is different from when I open the ST-Link in STM32CubeProgrammer (Frequency is 8000kHz) but it'd surprise me if that stopped it from working and I can't figure out how to change it (changing swoFrequency in launch.json has no effect).

I appreciate any help anyone might be able to give me. 

[Pavel A.]

https://www.designnews.com/embedded-systems/how-to-debug-a-microcontroller-using-visual-studio-code-vs-code-

[BobbyBeta]

Thanks, I'll read through it to see if it helps.

[BobbyBeta]

Well, I borrowed someone else's ST-Link and it worked. It had FW V3.J10.M3. I downgraded my ST-Link FW to the same revision and it now works. Apparently there's something about V3.J12.M3 that stops it from working with OpenOCD

[Pavel A.]

Note that ST has their own branch (or fork?) of OpenOCD, this is worth to use on STM32 instead of any other version.

[BobbyBeta]

Good to know. I think the codebase I'm working with is designed to work with Segger JTAG debuggers too so I'm not sure how much I can change at this point.

In some ways it's good to have a ton to work with when you start a new job. In other ways it means there's a ton to learn and you're unsure what you can change without affecting everyone else.