RAMPS 1.4
It is a Mega Pololu Shield, or RAMPS for short,designed
to fit the entire electronics needed for a RepRap in one
small package for low cost. RAMPS interfaces an Mega with
the powerful MEGA platform and has plenty room for
expansion. The modular design includes plug in stepper
drivers and extruder control electronics on an MEGA
shield for easy service, part replacement, upgrade-
ability and expansion. Additionally, a number of
expansion boards can be added to the system as long as
the main RAMPS board is kept to the top of the stack.

Mega 2560
Mega2560 is an ATmega2560 as core microcontroller
development board itself has 54 groups digital I / O
input / output terminal (14 groups do PWM outputs), 16
sets of simulation than the input side, group 4 UARTs
(hardware serial ports), using the 16 MHz crystal
oscillator. With the bootloader, download the program
directly via USB without having to go through other
external writer.