Reset button on nrf52840dk stopped working

[Oli]

It seems the "reset" button on my nrf52840dk doesn't do anything anymore. I believe this started happening after I enabled mcuboot in sysbuild. Is this expected?

[Oli]

After trying again with the j-link debugger (I found out I also had to keep the DK's usb plugged in for power), I was able to run `nrfjprog --recover` and flash it.

After running `nrfjprog --recover` using segger:

$ nrfjprog --recover                                                                master ✗
Recovering device. This operation might take 30s.
Erasing user code and UICR flash areas.
Writing image to disable ap protect.
$ nrfjprog --memrd 0x10001200                                                       master ✗
0x10001200: FFFFFFFF                              |....|

Unfortunately, even after recovering, if I try to build with the onboard debugger afterwards, it still fails:

Flashing build_dk to 1050227950
west flash -d .../firmware/build_dk --dev-id 1050227950 --erase

-- west flash: rebuilding
[0/10] Performing build step for 'mcuboot'
ninja: no work to do.
[1/10] Performing build step for 'firmware'
ninja: no work to do.
[4/10] cd .../firmware/build_dk/_sysbuild && /opt/nordic/ncs/toolchains/b8efef2ad5/Cellar/cmake/3.21.0/bin/cmake -E true
[6/10] No install step for 'firmware'
[7/10] Completed 'firmware'
[8/10] cd .../firmware/build_dk/_sysbuild && /opt/nordic/ncs/toolchains/b8efef2ad5/Cellar/cmake/3.21.0/bin/cmake -E true
-- west flash: using runner nrfjprog
-- runners.nrfjprog: mass erase requested
-- runners.nrfjprog: reset after flashing requested
-- runners.nrfjprog: Flashing file: .../firmware/build_dk/merged.hex
[error] [ Client] - Encountered error -102: Command read_device_info executed for 126 milliseconds with result -102
[error] [ Worker] - An unknown error.
[error] [ Client] - Encountered error -102: Command read_memory_descriptors executed for 25 milliseconds with result -102
Failed to read device memories.
[error] [ Worker] - An unknown error.
ERROR: JLinkARM DLL reported an error. Try again. If error condition
ERROR: persists, run the same command again with argument --log, contact Nordic
ERROR: Semiconductor and provide the generated log.log file to them.
NOTE: For additional output, try running again with logging enabled (--log).
NOTE: Any generated log error messages will be displayed.
FATAL ERROR: command exited with status 33: nrfjprog --program .../firmware/build_dk/merged.hex --chiperase --verify -f NRF52 --snr 1050227950

 *  The terminal process terminated with exit code: 33. 
 *  Terminal will be reused by tasks, press any key to close it. 

But flashing using segger works. So it seems there is an issue with the onboard debugger?

[Oli]

After flashing my firmware with segger:

-- west flash: using runner nrfjprog
-- runners.nrfjprog: mass erase requested
-- runners.nrfjprog: reset after flashing requested
-- runners.nrfjprog: Flashing file: /Users/redacted/code/alpha21/keyvo/firmware/build_dk/merged.hex
[ #################### ]   0.216s | Erase file - Done erasing                                                          
[ #################### ]   1.919s | Program file - Done programming                                                    
[ #################### ]   1.996s | Verify file - Done verifying                                                       
Enabling pin reset.
Applying pin reset.
-- runners.nrfjprog: Board with serial number 802000342 flashed successfully.

It seems, the nRESET register is correct:

$ nrfjprog --memrd 0x10001200; nrfjprog --memrd 0x10001204                          master ✗
0x10001200: 00000012                              |....|
0x10001204: 00000012                              |....|

When I connect to the onboard debugger, I still see VCOM0 and VCOM1 and application logs when I connect to VCOM0. Clicking the "Reset" button is not rebooting the MCU though.

[Oli]

Is the "Reset" button not working issue related to the issue with flashing using the onboard debugger? I am guessing there is a link between both issue but not sure what it is.

[Jørgen Holmefjord]

Sounds like there could be a problem with the firmware running on the debugger chip. By default, the reset button is not connected directly to the nRF54L15 chip (SB1 is open):

The button connects to the DBGR_RESET input on the debugger chip, which will trigger a reset of the nRF54L15 chip on the DK.

Can you try to install a newer version of J-Link, start J-Link Configuration, select the debugger and click "Update firmware of selected probes and programmers"?

Best regards,
Jørgen

[Oli]

I was able to update the debugger chip firmware but I'm still having issues with flashing.

error] [ Client] - Encountered error -102: Command read_device_info executed for 132 milliseconds with result -102
[error] [ Worker] - An unknown error.
[error] [ Client] - Encountered error -102: Command read_memory_descriptors executed for 25 milliseconds with result -102
Failed to read device memories.
[error] [ Worker] - An unknown error.
ERROR: JLinkARM DLL reported an error. Try again. If error condition