I have two boards for which I cannot flash the firmware.
I believe that I have a hard time putting them in DFU mode. I cannot tell if the board is in DFU Mode or not and it would be great to have a visual indicator to know.
I have created the proper connection string pointing the correct com port and issue the command to upload the firmware but keep on getting Error: NMP timeout
PC@DESKTOP-HG29JE3 MINGW64 /c/nfed/nrf/applications/serial_lte_modem/build/zephyr ((v1.3.2))
$ newtmgr -c port11 image upload app_update.bin
0 B / 169.02 KiB 0.00%Error: NMP timeout
What else can I do to flash the firmware? What am I doing wrong?