NRF52840 usb dongle factory firmware

[L.B.]

Hello,

is there a way to find the original (factory) firmware of the USB dongle with the NRF52840 chip?

I've erased the entire memory with a J-Link debugger and I've programmed my test programs but now I want to test some things with nRF connect for Desktop. And as I read, the nRF connect for Desktop requires that the dongle show up in the USB devices which is in my case doesn't happen.

Regards,

L. B.

[Jørgen Holmefjord]

Hi,

See "Revert to production bootloader" in nRF52840 Dongle Programming Tutorial.

Best regards,
Jørgen

[L.B.]

Thank you! I was able to reprogram my board successfully with a J-Link V9-G. However, in Linux, I had to firstly remove the "[" and "]" brackets from the file name for some reason. Then I did this:

JLinkExe -if SWD -Device nRF52840_xxAA -Speed 4000
connect
---> recover (with GUI)
loadfile ./graviton_bootloader_mbr_v1.0.1-nRF5_SDK_15.0.1-1.alpha_f76d012.hex
reset 
go
exit

and I had to power cycle the board (unplug, then plug back in again).

Regards,

L. B.