Hi,
hi have the same problem related here: https://devzone.nordicsemi.com/f/nordic-q-a/91890/nrf52-reports-two-jlink-cdc-uart-ports
With revision 2, UART show only one port com on windows device manager, and i have no problems. I use UART on window side with a Qt IHM, wich connect to the segger port com available.
Because windows report 2 identical JLink CDC uart port com, IHM connects to one of them. Sometimes it works because the connected one is the working one, and sometimes it fails because it's the one not working. If i uninstall faulty device driver in device manager (the faulty one cannot be identified, i have to test each), then UART is working well.
The very bad thing is when you switch ON/OFF the DK, the faulty port com is changing, so at each startup, we need to configure window device manager for fixing this strange behaviour.
This behaviour must be reproductible with uart example and any window terminal program.
Our demonstration product is unusable because of that, and we bought a few dozen of DK!
Do you have any update for the MCU firmware ?
Thanks,