Arduino Mega2560

The Arduino Mega 2560 is a microcontroller board based on the ATmega2560 (datasheet). It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. It has 54 digital input/output pins (of which 14 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 is compatible with most shields designed for the Arduino Uno, Duemilanove or Diecimila. Technical Specifications

• Microcontroller: ATmega2560
• Operating Voltage: V5
• Input Voltage (recommended): 7-12V
• Input Voltage (limits): 6-20V
• Digital I/O Pins:54 (of which 14 provide PWM output)
• Analog Input Pins: 16
• DC Current per I/O Pin: 40mA
• DC Current for 3.3V Pin: 50mA
• Flash Memory: 256 KB of which 8 KB used by bootloader
• SRAM: 8 KB
• EEPROM: 4 KB
• Clock Speed: 16 MHz

More info can be found on the Arduino website.