[nRF52 DK] PC does not recognize USB device anymore - LD5 fast blinking

[epetin]

HW: nRF52832 DK, PCA10040 V1.1.0, 2016.23

SDK: nRF5_SDK_15.2.0_9412b96

IDE: Eclipse configured according to https://devzone.nordicsemi.com/tutorials/b/getting-started/posts/development-with-gcc-and-eclipse

SoftDevice: ble_app_bps/pca10040/s132/armgcc

PC: Windows 8.1

nrfjprog version: 9.8.1

JLinkARM.dll version: 6.40

GNU Make 4.2.1 (Built for x86_64-w64-mingw32)

Issue description: after a couple of successful flashes from Eclipse using make, without any configuration changes the board stopped responding. LD5 on the board is blinking very fast. No J-Link devices can be seen in the Windows Device Manager (actually there's not even the category "Ports"), nor using the SEGGER J-Link Configurator:

I have also tried to boot into the "bootloader mode" but it does not change the situation - nothing can be seen on PC.

Does this mean that I need to arrange funeral to my poor Development Kit, or is there still some light at the end of the tunnel?

Thanks!

[AndreasF]

Hi.

I think you might have put your nRF52832 DK in Bootloader mode, can you check if the board shows up as "BOOTLOADER" when you power it up under your devices, like this:

If it does, copy this file(J-Link OB-SAM3U128-V2-NordicSemi 170724.bin) to the "BOOTLOADER" folder, turn the power of the board off and on, and it should work.

If it is not in Bootloader mode, you can try to force it into bootloader mode by holding the button IF BOOT/RESET in, and turning the power off and on.

Best regards,

[epetin]

Hi Andreas,

Thanks for the response. I have tried Bootloader mode (held IF BOOT/RESET while powering on) - now LD5 blinks slowly but nothing appears on the PC.

One thing I could try is to use another PC but I guess it's effectively the same as reinstalling all drivers, which I already did.

[epetin]

Hi,

Finally had the chance to try this on another PC but the problem persists. "USB Device Not Recognized" when starting in bootloader mode.

[AndreasF]

Hi.

Can you try to measure the supply voltage on the kit? It should be somrewhere between 2.8V - 3.3V

Best regards,

Andreas

[epetin]

Hi Andreas,

How do I measure the supply voltage? USB power via TP3 is 5,12 V. External supply pin voltage (not connected) is 1,12 V.

[AndreasF]

Hi.

You can measure for example at VDD located right to the IF BOOT/RESET button, and one of the ground holes at the top (GND).

Best regards,

Andreas

[inghowe83]

epetin

It looks like a HW issue which I encounter today, I visually check my board and notice U24 load switch is missing. By solder to short SB48 jumper the problem resolved

You could check the nRF52840-DK HW files schematic.

https://www.nordicsemi.com/Software-and-Tools/Development-Kits/nRF52840-DK/Download#infotabs

[epetin]

Thank you very much! I'll check this and let you guys know the result.

[inghowe83]

Take note that mine board is  nRF52840-DK HW, you will need to check your board HW schematic. I suspect its power related issue either with missing component/spoil component. The one which went missing for mine case is www.semtech.com/.../sc728.pdf

[julian24]

Hi.

This exact same thing happened to me today, I was flashing on my DK when suddenly it stopped being recognized by Windows. Did you ever manage to make yours work, or at least to find out what the issue was?

[Jared]

Hi,

Could you go through the steps in this thread and confirm that none of them fixed your issue?

regards

Jared 

[julian24]

Hi Jared,

I already followed that thread. I can't force the device's bootloader mode, it just behaves the same way. Also the 7th step link is broken, but i did all the other stuff.

edit: Also i measured tension and it's fine