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Connecting a LCD to an Arduino

So we need we need to connect
for the power :
Pin 2 (Vdd)  and pin 15 (BLA) +5V
Pin 1 (Vss), pin 5 (RW) and pin 16 (BLK) to be grounded
Pin 3 (Vo) use the diagram below in order to connect it

Pin3 Connection

(Download this dia schematic from here : Pin3Connection)

and for the data transmission the pins :
Pin 4 (RS), Pin 6 (E), Pins (11,12,13 and 14) D4 D5, D6, and D7

At this point we can use any 6 pins of arduino.

Looking at the LiquidCrystal class offered from arduino we can see that it's constructor sets (defines) all the needed pins.
So the command (constructor) LiquidCrystal(rs, enable, d4, d5, d6, d7) defines all the needed pins in order to function the LCD.

We have chosen to connect :

LCD Pin 4 (RS) at arduino pin 7
LCD Pin 6 (E) at arduino pin 6
LCD Pin 11 (D4) at arduino pin 5

LCD Pin 12 (D5) at arduino pin 4
LCD Pin 13 (D6) at arduino pin 3
LCD Pin 14 (D7) at arduino pin 2

So we have to use the command
LiquidCrystal lcd(7, 6, 5, 4, 3, 2);

to define the above pins.

In the next page we will see a much detailed schematic with all the pin considerations made in this page.