nRF52840 dongle is not detected by laptop.

[Atul Kumar]

Sir i have NRF52840 dongle i used many times works amazing.After i uploaded Gpio toggle program now dongle is like dead ,laptop is not detecting it, i can't see it in device manager not able to reset or DFU mode nothing is happening, what should i do ? Should i have to upload factory bootloader again ? If yes how to do that ? All drivers are up to date, all laptop ports are working fine.help me plz thankyou 

[Jørgen Holmefjord]

Hi,

Just to make sure, the red "breathing" LED on the dongle does not light up when you press the side-mounted RESET button on the DK (not the SW1 button)? Have you tested it on a different computer?

There is a Dongle programming tutorial that explains how to recover the dongle, but it should be very hard to brick it/corrupt the bootloader.

Best regards,
Jørgen

[Atul Kumar]

Yes RED led doesn't light up when i press side mounted reset button on the DK, and yes i have tested the dongle on different computer same problem, device input manager is not showing not even a yellow triangle. i don't know what happened VDD out is showing 5.12V. How to make it alive again ? Is there any method to know that dongle is fine just firmware problem has occurred ? 

[Jørgen Holmefjord]

You can try to reflash the original bootloader through a DK/J-Link debugger, by connecting pins the SWD pins. If this does not help, I suspect that the Dongle may have somehow been damaged (ESD/short circuit/overvoltage through USB/etc).

[Atul Kumar]

Okay will try to flash bootloader again.