invader7:
This lcd https://www.sparkfun.com/products/9395 needs only 1 digital pin to be connected to arduino ? Thanks
Yes that is correct. If you take a look at the "SerLCD v2.5 Datasheet" (found at your link) it says: "Only three wires -5V, GND, and Signal - are needed to interface to the LCD."
What do you mean "asynchronous serial" ? im very new sorry...
That's a fancy way of saying that the data does not have to be supplied at a fixed rate. For example, If you sending data from a keyboard you can pause between keystrokes and not mess up the communications.
Don