This firmware is compatible with the Arduino Mega and the newer Arduino Due. They have the same pinouts and form factor. They each have 54 digital input/output pins (of which 15 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button.
The Mega and Due can be programmed with the EZB firmware for a variety of capabilities when connected to ARC. The tutorial to program the firmware on this device can be found HERE. This hardware was added to ARC in this beta release.