RE: How to enable debugging on nRF9151 non-secure build?

davidoglu — Fri, 12 Dec 2025 15:11:07 GMT

Hi Simon,

I've tried a more modern development environment, VS Code. It really does many fancy things, like colorize my source code. But my hands are too old for this. I was mainly looking for a way to debug with GDB, and I had no luck running "west debug" on SDK v2.7.0 due to "Python dependencies were missing", even though everything was installed.

However, thanks to your suggestion to use the VS Code extension, I got some hints. I noticed how VS Code summons JLinkGDBServerCLExe and I recreated the procedure with just the terminal:

$ nrfutil device recover
$ JLinkGDBServerCLExe -device nRF9151_xxCA -if SWD -speed 4000 -nogui -singlerun

Then, in a separate terminal,

$ arm-zephyr-eabi-gdb
(gdb) target remote :2331
(gdb) file build/merged.hex 
(gdb) load
(gdb) mon reset
(gdb) file build/app/zephyr/zephyr.elf
(gdb) b main
(gdb) c
Continuing.
Breakpoint 1, main () at src/main.c:437
437        ...
(gdb)

Just works!!

RE: How to enable debugging on nRF9151 non-secure build?

Simon D-M — Fri, 12 Dec 2025 10:19:15 GMT

Hi Denis,

What you are doing is a super manual way of debugging. I would recommend you looking into this "Dev Academy - Debugging". This is an easier way to debug.

Here is also some documentation on debugging a non-secure project (link).

By default, you can only debug the non-secure part of the application. If you want to debug the secure part, you have to enable the Trusted Firmware-M debug symbols.

If you are using VS Code with the nRF Connect for VS Code extension, This will be done automatically for you when you debug through the extension.

Also, if you want to debug the program with ozone, the VS Code extension should detect that zone is installed and should show the action "Debug with Ozone".

I hope I was able to help you.

If you need more information, fell free to ask!

Best regards,

Simon D-M