If you try to use the USBtinyISP USB AVR programmer as a regular user in Fedora, you will get a permissions error like the one below.
avrdude -p m328p -c usbtiny -e -U flash:w:test.hex avrdude: Warning: cannot open USB device: Permission denied avrdude: Error: Could not find USBtiny device (0x1781/0xc9f) avrdude done. Thank you.
In order to use the USBtinyISP without becoming root you will need to add a udev rule that gives regular users permission to use the device.
su
echo "SUBSYSTEM==\"usb\", ATTR{product}==\"USBtiny\", ATTR{idProduct}==\"0c9f\", ATTRS{idVendor}==\"1781\", MODE=\"0666\"" > /usr/lib/udev/rules.d/99-custom.rules
udevadm trigger
You should now be able to use the USBtiny with avrdude as a regular user.
