Just as a tip for Arduino newcomers, if you want to put the UNO R3 into DFU mode [1], just bridge these two pins together with a jumper or a cable for a moment:

Just as a tip for Arduino newcomers, if you want to put the UNO R3 into DFU mode [1], just bridge these two pins together with a jumper or a cable for a moment: ____________________ | o ··········· RESET ---> + · · GND -----> + · · _|____ | | | USB | |______| | | Then, if you want to use the dfu-programmer[2], you need to apply a patch[3] to make it work with the R3. Being myself a complete newbie, I found it time consuming to reach the state in which I knew how and what to do just to upload a new firmware. [1]: If you want/are interested in playing with Arduino as an USB device. [2]: http://dfu-programmer.sourceforge.net/ http://dfu-programmer.sourceforge.net/ [3]: https://aur.archlinux.org/packages/dfu-programmer/ https://aur.archlinux.org/packages/dfu-programmer/