can't open device "/dev/ttyACM0":

[Kilroywashere]

Anyone good with Linux?

avrdude: ser_open(): can't open device "/dev/ttyACM0": Permission denied


I think this means It does not have admin permission to open  the usb port?

I just started with Linux so ....


How do i allow permission to the usb?

[ataradov]

First of all check that /dev/ttyACM0 actually exists. Do something like 'ls -la /dev/ttyACM0' and look at the output. After that things start to differentiate depending on a distributive.

You may need to add your used to some group (often called 'dialout').

I typically just create a UDEV rule to let anyone use the port. Again, depends on the distro. In Debian based it will be something  like this. Create a file /etc/udev/rules.d/90-ftdi-cable.rules (name it whatever you want, of course). The contents of the file should be something like this:

Code: [Select]

ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6001", MODE="0666"
Substitute correct VID and PID for your device. Unplug and re-plug the device. This will give everyone RW access.

[particleman]

Are you trying to use Arduino by any chance?

[hamster_nz]

Permission denied - so as you say the device exists, but you can't access it.

Try either adding yourself to the dialout group (and then signing back in so you get the new permissions, or 'sudo chmod 666 /dev/ttyACM0'.

There is a chance that another process is using it. Try 'sudo fuser /dev/ttyACM0' to see what process id might be guilty, and 'ps -ef' to list processes.

[bingo600]

Usually you need to add your user to the group : dialout
In order to access the serial devices.

/Bingo

[MLXXXp]

In addition to adding yourself the the dialout group, (at least with Ubuntu) sometimes you have to disable Modem Manager, which grabs the port and makes it unavailable.

Check if Modem Manager is enabled:
systemctl list-unit-files | fgrep ModemManager

Disable:
sudo systemctl disable ModemManager.service