The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. It has 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. 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.
Features
Pinout: added SDA and SCL pins that are near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board. In future, shields will be compatible both with the board that use the AVR, which operate with 5V and with the Arduino Due that operate with 3.3V. The second one is a not connected pin, that is reserved for future purposes.
Difference USB controller version:
Because Atmel is moving more and more of their production capacity to surface mount ICs, the DIP packaged ATmega is becoming more and more difficult to get. The board is identical to the PTH version of the Uno, but you won't be able to remove the ATmega without some hot-air. This change shouldn't affect most users. Besides - when was the last time you managed to destroy an ATmega and needed to repair an Arduino board? Those things are nearly indestructible.
*Please note that the boards have a CH340G USB-Controller rather than ATmega16 like regular MEGA2560. They are recognized on Linux without any additional drivers. Mac OS and Windows users may need to install an additional driver.
Specifications
Package List: