Brand new board . Can't flash - "No operations possible for device. If the device is a MCUboot device make sure it is in the bootloader mode" error

Hey all,

We've just received our first article of a new PCB based on Fanstel BT840F (nRF52840, https://www.fanstel.com/bt840)

I'm trying to flash it with a demo app using DEBUG OUT port on nRF52840DK (P20) but get the following error message in the Programmer app:

"No operations possible for device. If the device is a MCUboot device make sure it is in the bootloader mode" error

This is how things are connected

Config 1 - PCB powered by the DevKit

Config 2 - PCB is powered externally

Both configurations give the same results.

Also,

Can someone clear out what GND_DETECT is used for (the users manual says nothing about it)

Thanks for any advice.

Related