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My serial port is located at /dev/ttyUSB0, and every time I want to access it after waking up my computer or starting it (Ubuntu 12.04), I have to run sudo chmod 777 /dev/ttyUSB0 to grant myself access to the serial port.

Is there any way to give myself access to it by default? This is getting very annoying. Thanks.

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I believe that all /dev/tty* are owned by root.tty, so you could add yourself to the tty group.

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Do you have any more instruction on how to do that? Thanks! – capcom Oct 22 '12 at 13:15
@capcom sudo adduser <user> tty will add <user> to the group tty. – Darth Android Oct 22 '12 at 14:29
/dev/ttyUSB0 permission denied 【access your device permanently.】

Problem: /dev/ttyUSB0 permission denied. You're not root, has no permission. Generally, do this way:

$ sudo chmod 777 /dev/ttyUSB0

This isn’t very safe, strictly speaking, nor is it permanent. The change will need to be repeated every time you reboot the computer or unplug and reconnect the device.

 $ sudo usermod -aG dialout username

username is your username. Add this user into your dialout userGroup. Log out your linux and you can access your device permanently.

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