Bricked debugger on nRF54L15-DK

[Nick Stoughton]

I just received a new 54L15DK and was attempting to port a simple 5340 project to it. The first time I attempted to flash it, it _looked_ like it was successful:

[10/10] Generating ../merged.hex
-- west flash: using runner nrfutil
-- runners.nrfutil: reset after flashing requested
Using board 001057782011
-- runners.nrfutil: Flashing file: /home/nick/work/eargo-charger-fw/projects/novum/build/merged.hex
-- runners.nrfutil: Erasing pages touched by firmware
-- runners.nrfutil: Programming image
-- runners.nrfutil: Verifying image
-- runners.nrfutil: Reset
-- runners.nrfutil: Board with serial number 1057782011 flashed successfully.

However, from this point on, the debugger refuses to accept commands. I suspect I flashed the debugger (a 5340) rather than the 54L15, since I had not fixed my sysbuild.conf. Is there any way to reflash the debugger?

--

Nick

[rba]

I have a similar issue. I just received my nRF54L15-DK v. 0.9.2 a couple of days ago. Yesterday, I managed to flash and get the blinky example to work. Today, I cannot reach the board anymore through VSCode.

What I've tried

- Measured VBUS: 5V, VDDIO 1.8V;

- A different USB-C cable. No change. The same USB-C cable can debug other boards;

- nrfjprog --recover: ERROR: No debuggers were discovered;

- I _can_ reflash the target nRF54L15 if I connect an external J-LINK debugger in the DEBUG IN/TRACE header, but the expected LED0 does not flash anymore;

- I _cannot_ use the built-in debugger to debug external targets via the DEBUG OUT header;

- I cannot find the board in the Board Configurator from nRF Desktop

In my case, the LD1 flashes irregularly for 1-2 seconds when I connect it to my macbook, but after that it remains off. The same happens if I connect it to a USB-C power brick. Once in a while it will flash briefly and stop again. I suspect the debugger is bricked, but I'm not sure why.

I didn't change anything from yesterday to today -- I did leave it plugged in overnight, but I'd be surprised if that's enough to damage it.

Are there any more steps I can do to try and recover it?