XMEGA A1U Xplained Pro contains an Embedded Debugger (EDBG) that can be used to program and debug the ATxmega128A1U using the Program Debug Interface (PDI). The Embedded Debugger also include a Virtual Com port interface over UART, an Atmel Data Gateway Interface over SPI and TWI and it monitors four of the XMEGA GPIOs. Atmel Studio can be used as a front end for the Embedded Debugger.