Sam Ellenby

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10 years, 8 months ago.

Dead NRF51822

So, I got my NRF51822-mkit and everything was going great until it suddenly stopped working this weekend :-( I wasn't doing anything particularly taxing just toggling some I/O.

The drive comes up on my computer, but when I try to copy files across to it, it sits 'discovering' the file, until eventually the mbed disconnects from my computer.

I've tried various stuff: Vcc seems ok although a little low at 3V due to what I assume is the diode drop? Restoring my computer to a point before driver installation (then reinstalling). I can upload a non .hex file and get the expected fail.txt file. I've used two USB cables (one brand new), with no joy.

Any suggestions you have on how I can unbrick my NRF51822? Is there an ISP mode like the LPC1768?

UPDATE:

After hassling everyone willing to listen (hint, social media is a great way to get customer service attention). I got a reponse from Nordic Semi, they supplied me with an updated mbed interface firmware. This enables the user to wipe the NRF51822 by holding reset for 5s, effectively releasing it from its 'dead' state.

I tried it this morning and it has bought my dead board back to life. Hopefully this change will get released to a wider audience before more of us have this issue.

Question relating to:

Last updated: 27 Aug 2020
The nRF51822-mKIT is a low cost ARM mbed enabled development board for Bluetooth® Smart designs with the nRF51822 SoC. The kit gives access to all GPIO pins via pin headers …
posted by Runar Skjerve 25 Apr 2014

Thanks Runar, your support team was helpful and efficient. Please pass on my thanks.

posted by Sam Ellenby 25 Apr 2014

This fix worked for me. I am up and running again.

...kevin

posted by Kevin Braun 25 Apr 2014

6 Answers

Runar Skjerve
10 years, 8 months ago.

Hi,

A fix for this problem is available here: https://devzone.nordicsemi.com/index.php/mkit-dead. Note that this is a beta version and that an official release will be made next week.

Best regards,

Accepted Answer
Kevin Braun
10 years, 8 months ago.

I ran into this same issue about a week ago.

http://mbed.org/questions/3177/nRF51822-stopped-downloading-programs/

I have a ticket open at Nordic regarding this problem.

BTW: The Nordic support crew has been on vacation the past week or so. They should be returning by tomorrow.

...kevin

Thanks Kevin. Hopefully they will have something helpful to suggest. Please let me know what they say.

posted by Sam Ellenby 23 Apr 2014

I found this thread on the NRF forums https://devzone.nordicsemi.com/index.php/nrf51822-is-so-easy-to-be-damaged

It sounds very similar to the problem I am having at the moment. Unfortunately, I am guessing the mbed interface doesn't support this tool. That and I am unable to download the SDK without buying the nordicsemi evaluation kit.

posted by Sam Ellenby 23 Apr 2014
Maurizio Conti
10 years, 8 months ago.

Also I have the same problem.

The green LED stops flashing. The drive has disappeared from Windows Explorer.

I opened a ticket with Nordic.

Can I reset the bootloader?

Eric Hoffstetter
10 years, 8 months ago.

Were you guys able to program the kit at all? Out of the box mine shows up as a usb drive and I see the mbed.htm file there, but when I compile and download the file to the thumb drive it flashes the USB led and the drive remounts, but the nordic chip doesn't seem to do anything. Even with the mbed_blinky sample I get nothing.

Your problem sounds very different to mine. I suggest you try pressing reset a few times, to see if the board springs into life.

posted by Sam Ellenby 25 Apr 2014

It seems like the mbed interface firmware is a bit janky on this one. I tried using the kit at work with the maxthon browser and noticed it restarted before the hex file finished downloading. So I downloaded the firmware to a separate directory and then copied it to the kit after it downloaded. Suddenly everything worked. I think it's trying to flash the placeholder file some browsers create when they start downloading a file.

So if you can't get anything to work, try downloading your hex files to a different dir and copying them to your mbed after they have downloaded.

posted by Eric Hoffstetter 26 Apr 2014
William Morrow
10 years, 8 months ago.

I just Bricked mine last night but it was acting a bit weird with Windows 8.1 as the drive was connecting and disconnecting every second, but a reboot of windows before connecting would help. then the connection seemed to beak half way while transferring a hex file and the dev kit stopped working. Then i tried pressing the reset button for 5 seconds and the boot loader drive appeared for one second.

I tried with my Mac and the mbed loader drive appeared stable but i don't have the firmware to load. I opened a support ticket last night asking for the firmware, hopefully i will get a response.

Janek Mann
10 years, 8 months ago.

Hmm, interestingly I seem to have the same issue. My suspicion is that the nrf51 is executing some code that is resetting the chip and stopping the debugger from connecting. The regular nrfgo interface has a button for "recovery" for that situation but I don't know how that access that through the cmsis-dap... (and unfortunately the board designer didn't place an external jtag interface for the nrf51...)

I'm both reassured and concerned that someone else is suffering the same symptoms. Part of me believes I have in some way blown up the chip. Although in my 6yrs as an EE, this would be the first time I've blown up an MCU.

I don't have a scope at home, If i had one, I wonder what the SWD lines are up to when this is happening.

posted by Sam Ellenby 22 Apr 2014

I think it's rather unlikely you (or I) physically damaged the chip... I have abused some of them quite severely without any ill effect.

posted by Janek Mann 22 Apr 2014