Fixing failure of software upload to ┬ÁController

December 5, 2019 - Reading time: ~1 minute

If uploading software from the Arduino IDE or the commandline via avrdude to a microcontroller like an Arduino or an ESP8266 fails due to missing access rights ("Permission denied"), what helps is either

sudo chmod a+rw /dev/ttyUSB0

or adding the user to the group "dialout":

sudo usermod -a -G dialout theuser

See: https://forum.arduino.cc/index.php?topic=495039.0