The processor board of M2 contains the brains and the communication circuitry. It features 6 LEDs (5 one-color and 1 RGB LED), 4 switches (2 user switches, RESET and ERASE), an EEPROM, an SD car socket, a Native USB port (that can act as both a USB device or host), and a XBee form factor socket,
M2 uses the same processor as the Arduino Due.
More information, including original Due schematics found here: https://www.arduino.cc/en/Main/ArduinoBoardDue
Here is the link to the datasheet: http://www.atmel.com/Images/Atmel-11057-32-bit-Cortex-M3-Microcontroller-SAM3X-SAM3A_Datasheet.pdf