USB Flashing for MeshCore

Note: use a DATA USB cable. Marked with the "fork" on connector. Not a power-only cable.

Getting "Failed to execute 'open' on 'serialport'" on USB connection?

sudo setfacl -m u:YOURUSERNAME:rw /dev/ttyACM0
sudo chmod 777 /dev/ttyACM0

Note: you USB dev *might* differ from ACM0