I was trying someof the examples RIOT has. The problem is that RIOT’s flash uses /dev/ttyACM0 by default and when I connect the nRF52840-dongle it’s assigned a port /dev/ttyACM1.
This results in failing to flash!! Has anyone idea how to specify port while flashing? like with
make flash BOARD= nrf52840-dongle -p /dev/ttyACM1