squizzatoandrea:
Hi, thanks for your answer.
I'm new of arduino: can you explain me better what does it mean?
What is a mega? 40 IO Pins?Thank you very much.
Andrea
The Mega is another Arduino development board with a different microcontroller chip than the Uno (the most common Arduino board). The main reasons to use the Mega instead of the Uno are the larger memory (both for program and RAM) and more I/O pins.
IO or I/O stands for Input / Output pins, these are pins that can function either as inputs or outputs (depending upon how they are configuring and used in a sketch).