Segmentation fault (core dumped) on custom nRF52840 board.

[Nikita P.]

Hi.

I'm having Segfault issues with our company's custom boards based on nRF52840 chips.

I do several re-flashing with J-Link EDU Mini Programmer on a daily basis with nRF Command Line tools on Ubuntu (current nrfjprog version is  10.6.0 and JLinkARM.dll is 6.70.), however now I have up to four boards with the same Segfault issue. I haven't yet noticed any way to reproduce the issue.

Every nrfjprog command return the same Segfault error. Tried to fix the issue with different solutions:

• Apply different power souces.
• Using J-Link EDU Programmer.
• Updating nrfjprog to 10.7.0 and JLink to 6.70a.

I've captured logs for nrfjprog --recover command:
log.log

[Kenneth]

Hello,

I recommend to use the jlink version that is bundled with the specific nrjprog installer by default. This is the combination that is tested. I believe there is an issue with 6.70 that they are currently debugging. 

Best regards,
Kenneth

[Nikita P.]

Ok. I re-installed nRF Command Line tools (10.6.0) with bundled jlink, and still having Segfault error. With 10.7.0 version I get:

ERROR: Cannot connect to any nRF device. Please make sure a device is
ERROR: connected to the debugger and supplied.

[Kenneth]

The J-Link EDU Mini will only work with approx 3.3V if I remember correctly, I am not sure how you have supplied your board, but if you are using high voltage mode, then REGOUT0 default value is 1.8V when UICR is erased. Can that be the problem here?

I recommend to get hold of a Windows computer and test, just to rule out if OS related or not.

If you are in production of some sort, then it could be interesting to understand the failure rate, and possible if they have been programmable at any time, in case it can be an ESD issue and/or soldering issue.

Best regards,
Kenneth