Windows not recognizing nRF52840 DK when connected via USB

[RoyceThomas]

Hi,

When I connect my nrf52840 DK to the PC via USB, initially it shows up as a drive, but then If I try to flash it from nrf Connect for VS Code, It gets disconnected and after that, the board is not getting recognized.

In the device manager, it is coming up as "Nordic Semiconductor DFU"

Things I tried:

1. Checked with different USB cables.

2. Reinstalled nrf Connect for Desktop and Jlink driver.

3. Connected the DK on another PC, and it gets recognized.

4. Connected another nrf52840 DK and I'm facing the same issue.

5. Tried to press the IF BOOT/RESET button while power cycling the kit and it shows up as a Removable Storage Device named "BOOTLOADER". Then I dragged and dropped the Jlink interface MCU firmware. Diconnected the board and when I connect again the issue still persists.

6. Tried "nrfjprog --deviceversion", but it returns "ERROR: No debuggers were discovered".

My guess is it is something related to my PC and not the DK itself. What else can I try? Is there any possibility to reset the board?

[Naeem Maroof]

Hi Royce,

Thank you for contacting DevZone at NordicSemi.

Sorry to hear that you are struggling to connect a DK with you PC (let's call it PC1) and thank you for trying different solutions.

As per your information:
1) the cable is good (no problem in that)
2) software installation is good / updated (no problem in that)
3) connecting DK to other PC (let's call it PC2) is good
4) connecting another DK shows same issues

As per #3, the DK as well as the PC2 are good

for #4, you are connecting a different DK to PC1? if this is the case then it confirms that the problem is not with the DK and infact with your computer (PC1). I am not sure what problem it is, but could be USB port and/or driver issue.

Other things which you could try (at your own choice) are:
-update you windows operating system
-update your device drivers
-restart your pc
-hook DK into another USB port (if available)
-check software & driver on both PCs are same

What do you mean by "possibility to reset the board"? You have already updated MCU firmware. 

with regards,
Naeem

[RoyceThomas]

Hi Naeem,

Thanks for the reply. I updated my windows OS and found that now my device is getting recognized by the nrf programmer and I can flash using the programmer tool.

But, the board gets disconnected when I try to flash using nrfjprog or from nrf Connect for VS Code. Even if I try "nrfjprog --deviceversion" the board gets disconnected. After that, I have to close nrf connect for desktop, toolchain manager, etc, and reconnect the board to the PC.

Don't know if it helps, but I was able to communicate with the board using the JLink commander tool. Are there any useful JLink commander commands that might be helpful to debug the issue further?

I don't know what is causing this weird issue. Please help.

Thanks,

Royce

[Naeem Maroof]

Hi Royce,

Good to know that updating the OS fixed some of the issues. 

Which Jlink version and nrf connect version you are using? You can try updating these as well.

Thanks,

Naeem

[RoyceThomas]

 Hi Naeem,

The JLink driver version is 1.34.0.44950 and the nrf connect version is 3.12.0. I tried updating all of them but no luck.

[Naeem Maroof]

Hi Royce,

As you have updated windows as it solved some of the issues, could you do a fresh installation of everything (nrf command line tools, VS Code and NCS using nrf-connect-desktop).

You may follow this guide: nRF Connect for VS Code, 1: Installation - YouTube

Thanks, 
Naeem