improved softdevice debugging

[Jonathan]

I remember reading somewhere an article on how debugging with softdevice was going to be easier, with the debugger doing something along the lines of actually not stopping execution when hitting a breakpoint, but rather executing a loop in the background so your code is effectively stuck, but softdevice can keep functionning normally.

Would anyone know where to find information about that? Especially, what are the conditions to get this behaviour (JLink patch, nRF52.....?). Thanks!

[leonwj]

Hello Jonathan,

I believe you are referring to the Monitor Mode Debugging (mmd) capabilities of the Cortex-M3/M4 chipset. The following link presents a starters guide to get up and running. There are also a couple of additional blog postings on the Nordic site that you may want to read as well. Note that mmd is not available on the nrf51xxx chipset as this conains a cortex-M0.

Additionally, you should ensure that your J-Link software is upto v6.x as it allows the softdevice to correctly work with the amended mmd vector table as well as the provision of a few mmd related bug fixes/enhancements.

This link also provides a basic overview of the mmd capabilities within the SoC.

Regards,

leonwj

[Jonathan]

Thank you very much, that's exactly it. I knew I couldn't use it yet, but didn't remember why for sure, and that is because we're on nRF51. But also planning on switching to nRF52, so that's a reason to speedup the switch!

[awneil]

leonwj said:

The following link presents a starters guide to get up and running.

That link - https://devzone.nordicsemi.com/blogs/877/monitor-mode-debugging-revolutionize-the-way-you-d/ - no longer works.

Is the article still available?

[Jørgen Holmefjord]

Unfortunately, that blog post is no longer available. There is an updated "guide" available here.

[awneil]

See also: https://devzone.nordicsemi.com/b/blog/posts/segger-embedded-studio-part-2-monitor-mode-debuggi

And: https://devzone.nordicsemi.com/b/blog/posts/monitor-mode-debugging-with-j-link-and-gdbeclipse 

[awneil]

leonwj said:

Additionally, you should ensure that your J-Link software is upto v6.x

Note that it needs to be a J-Link PLUS, ULTRA+, or PRO - the on-board J-Link on nRF dev kits is not licensed for MMD:

See also the note in this blog: https://devzone.nordicsemi.com/b/blog/posts/monitor-mode-debugging-with-j-link-and-gdbeclipse - particularly if you are on a non-Windows platform!