This is Due AT91SAM3X8E ARM Cortex-M3 Board 84MHz 512KB Board compatible with Arduino.
The Due is a microcontroller board based on the Atmel SAM3X8E ARM Cortex-M3 CPU. The Due
Arduino AT91SAM3X8E ARM Cortex-M3 Board is the first Arduino board based on a 32-bit ARM
core microcontroller. It has 54 digital input / output pins (of which 12 can be used as PWM
outputs), 12 analog inputs, 4 UARTs (hardware serial ports), a 84 MHz clock, an USB OTG
capable connection, 2 DAC (digital to analog), 2 TWI, a power jack, an SPI header, a JTAG
header, a reset button and an erase button.
The board contains everything needed to support the microcontroller; simply connect it to a
computer with a micro-USB cable or power it with an AC-to-DC adapter or battery to get
started. The Due is compatible with all Arduino shields that work at 3.3V and are compliant
with the 1.0 Arduino pinout.
The SAM3X has 512KB (2 blocks of 256KB) of flash memory for storing code. The bootloader is
pre-burned in a factory from Atmel and is stored in a dedicated ROM memory. The available
SRAM is 96KB in two contiguous banks of 64KB and 32KB. All the available memory (Flash, RAM,
and ROM) can be accessed directly as a flat addressing space.