nRF52840 DK Debugger and USB Detection Issue.

RE: nRF52840 DK Debugger and USB Detection Issue.

warning — Mon, 15 Sep 2025 07:10:46 GMT

Hey, Thank you. Looking forward to it. I am available for a video call if needed as well.

RE: nRF52840 DK Debugger and USB Detection Issue.

Simonr — Mon, 15 Sep 2025 06:40:59 GMT

Let's handle this issue in the ticket you created here: nrf52840 DK not connecting. none of the inputs connect

Best regards,

Simon

RE: nRF52840 DK Debugger and USB Detection Issue.

warning — Sun, 14 Sep 2025 15:05:28 GMT

Can someone from support get on this issue, we can't continue with our project??

RE: nRF52840 DK Debugger and USB Detection Issue.

warning — Sun, 14 Sep 2025 14:43:10 GMT

any results???? same issue.

RE: nRF52840 DK Debugger and USB Detection Issue.

Simonr — Mon, 13 Jan 2025 12:08:28 GMT

Have you tried toggling the ON/OFF button while the micro-USB is plugged in? Do you see the same behavior then? What is the USB cable connected to on the other side? A computer directly or a USB hub? Also, please confirm that this is a USB cable that's able to transfer data and not just power.

Best regards,

Simon

RE: nRF52840 DK Debugger and USB Detection Issue.

Rahul Chavda — Fri, 10 Jan 2025 06:14:58 GMT

I am facing the same issue. The LED5 on my DK board blinks for a short time and then turns off. Please find the attached video.

devzone.nordicsemi.com/.../IMG_5F00_7861-_2800_1_2900_.mov

RE: nRF52840 DK Debugger and USB Detection Issue.

Simonr — Thu, 09 Jan 2025 13:54:11 GMT

Hi again Manoj

Any chance you can try on a Windows machine for example? It sounds like the issue is still that the IMCU firmware isn't correctly flashed to the debugger, and I haven't heard of anyone using Linux Lite in the past, so I just want to make sure this isn't a OS issue. Did the nRF52840 DK work at one point, but then started misbehaving at some point, or has it been like this all the time. Could you also share the build code of the board (on the white sticker there are three lines of numbers below "PCA10056") that might be helpful.

Best regards,

Simon

RE: nRF52840 DK Debugger and USB Detection Issue.

manoj_patil — Thu, 09 Jan 2025 05:29:52 GMT

Hi Turbo J and Simon,

Thank you for your suggestions! I followed the procedure to reflash the Interface MCU firmware as described in the documentation and the link provided. However, the issue persists.

Here’s the current situation:

The debugger LED (LED5) blinks briefly when I plug in the USB but then turns off completely.
The four LEDs connected to the controller are still dimly blinking, even though no code is running.
The board is not recognized as a USB device in Linux (lsusb does not list it).

Thank you for your continued support!

Best regards,
Manoj

RE: nRF52840 DK Debugger and USB Detection Issue.

Simonr — Wed, 08 Jan 2025 14:19:41 GMT

As Jörg says, try reflashing the IMCU firmware. Here's the link to the download page he mentions. Please reach out if this doesn't help.

https://www.nordicsemi.com/Products/Development-hardware/nRF52840-DK/Download#infotabs

Best regards,

Simon

RE: nRF52840 DK Debugger and USB Detection Issue.

Turbo J — Tue, 07 Jan 2025 15:31:40 GMT

Try reflashing the "Interface MCU firmware" (under Downloads from the DK website). You can enable the DK bootloader by holding the reset button on power-up/pluggin the USB cable in.

Procedure should be documented in the manual.