Add serial port permission to user, on Ubuntu Linux.

This video show how to fix error of avrdude: ser_open(): can’t open device “/dev/ttyACM0”: Permission denied for Arduino IDE on Ubuntu Linux, by adding serial port permission to user.

Install Arduino IDE 1.8.9 on Ubuntu 18.10 and set permission for serial port https://arduino-er.blogspot.com/2019/04/install-arduino-ide-189-on-ubuntu-1810.html

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