J-Link issue with nRF21540-DK

[pixbroker]

I am trying to use a nRF21540-DK on macOS and I am having some issue with the J-Link thats on board. 

The J-Link FW reports as: 

Firmware: J-Link OB-nRF5340-NordicSemi compiled Oct 30 2023 12:13:06

However, the DK does not show up in VSCode correctly. Additionally, it shows up in the macOS finder as "J-Link" but only briefly, as it seems to be rebooting and therefore ejecting. This happens in a constant loop.

Disabling the J-Link MSD works (it no longer shows up on finder), but is otherwise still unusable as DK.

I assume there is something wrong with the J-Link FW.

I see there there is a J-Link FW image (.bin) on the nRF21540-DK website. However, im unable to get the DK into boot loader mode. Holding the reset button while powering up the DK never leads to a flashing LED5 nor does it show up in finder as "BOOTLOADER" (msdenabled again).

Does anyone have some trick how to flash the correct (nordic) FW to this DK's J-Link?

[PaKa]

The BIN file is for the older NXP based OBD (JLINKs) so won't work with your board. The new boards don't have the push button to DFU solution, they only update from the SEGGER tools. Can you test the board on a Windows computer and see it it pops up there as normal and updat the code there? The SW version you have should be the latest for that board.