This is an USB to UART example based on the LUFA library. It makes all seven UARTS of the ATxmega128A3U available as virtual COM ports via USB. They can then be used as whatever the user might want. At the moment only 5, 6, 7 or 8 bit are supported at all rates. A 9 bit communication is not implemented, yet. Since the firmware uses the AVRs CPUID to generate a serial number for the USB, it is possible to have muliple of these devices at the same host computer. In Linux the first created terminal device (ttyACM0, if there is no other terminal device already installed) will be for USARTC0. The second for USARTC1, the third USARTD0, and so on. (The last created terminal will be for USARTF0, since the AVR has no USARTF1.) Users of Microsoft Windows may want to use the driver "ATxmegaUSBtoUART.inf". The Mapping between UART and COM port number is done at installation time and can be investigated in the device manager. Stephan Baerwolf (matrixstorm@gmx.de), Schwansee 2014