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I faced a strange problem today. I can't open my serial port and it says permission denied!! It's strange because I checked and I member of the dialout group! I'm using arduino.

marked as duplicate by N0rbert, Community Apr 17 '18 at 12:33

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  • Could you add ls -l /dev/tty* to the question. I expect that arduino port is created in root group not dialout by default. – user.dz Apr 16 '17 at 11:02

In general it's always helpful to write out all the commands and their results.

For Arduino in particular, what does this command return?

$ ls -l /dev/ttyACM*

If it indicates less permission, you might want to give yourself read and write access, e.g.:

sudo chmod 600 /dev/ttyACM0
  • To thoever downvoted; it'll be always helpful to improve (future) answeres and visitors if you leave comments why you had to downvote. Thanks. – IsaacS Apr 18 '18 at 16:31

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