Ttyusb0 permission denied

[hansharms]

I tried to connect esp32C3 board. (ubuntu version 24.04). Serial monitor did not connect:
Error:
Port monitor error: command open failed: Permission denied. could not connect to /dev/ttyUSB0 serial port.

[ledsyn]

Check that your user is in the same group as /dev/ttyUSB0:

#> ls -l /dev/ttyUSB0
#> crw-rw---- 1 root uucp 4, 93 Apr 13 00:45 /dev/ttyUSB0

In my case the group is uucp, but it can be dialup as well. Now check that your user is a member of that group:

#> groups

If not, add your user to the group:

#> sudo usermod -a -G <group> <user>

Reboot.

Something else that can prevent you from accessing the serial port is a software package called brltty. It's for blind people, a braille terminal. Unless you need it, it can be removed by

#> sudo apt-get remove brltty

Reboot.