Dead-ish nRF52-DK anything else I can try?

[Dom O]

One of my nRF52-DK started to act oddly - very brief message in red type flashed up by nRFgoStudio on programming a few times - unfortunately too fast for me to read.

Now Windows 10 cannot connect to that nRF52-DK at all. (but with Ubuntu it shows with lsusb - erratically)

1. I've tried reflashing the bootloader on the nRF52-DK - goes into bootloader fine, reflashes fine - but still cannot connect to it outside of bootloader mode.

2. Ive tried this nRF52-DK on another machine - exactly the same behaviour. I've tried other nRF52-DK in both machines - and they behave normally.

Anything else I can try before consigning this board to the rubbish?

[Dom O]

Hi Martin - and thanks for the very quick reply!

From your checklist:

1. My faulty nRF52-DK does not show in Device Manager (and another known good DK does).

2. Swapped USB leads between the faulty and known good device - no change.

3. Same behaviour as in 1 and 2 above, on another computer.

4. The faulty DK does show up as BOOTLOADER and I can reprogram the bootloader firmware.

5. Supply voltage measures 2.79V on both faulty and known-good DK's (I don't have access to a calibrated voltmeter).

6. nrfjprog reports JLinkARM version 6.20b

7. JLink Commander cannot see the faulty DK, but can see the known-good DK.

One final thing - I've noticed the faulty DK is V0.90 2015.41 - so I presume a fairly early one, is this of any significance?

(I've several DK's - I'm pretty sure this one was given to me at Nordic Tech Tour. I have another V0.90 DK that works correctly though)

[Sigurd]

Are you using any kind USB hub? I've experienced some issues with J-link and USB hubs, and I recommend connecting the DK directly to the computer's USB ports if you are having these kind of issues.

The V0.90 version of the nRF-52832 DK uses a Engineering B version of the nRF52832 IC , and we do not recommend any development being done on engineering samples. So if you have any newer versions(1.1.x) of the DK, I would recommend to use those instead.