This use for Hitachi HD44780 based, or compatible. You can learn how to interface LCD Module with Arduino Board.


Need:

• Arduino Board Duemilanove ATmega328.
• LiquidCrystal.h library
• LCD Module 16x2, 16pins where same with pin layout formed Hitachi HD44780.
  
  

• LCD Module PIN-out Ground VCC (+5V) Contrast adjustment Register Select (R/S) Read/Write (R/W) Clock (Enable) Bit 0, DB0 Bit 1, DB1 Bit 2, DB2 Bit 3, DB3 Bit 4, DB4 Bit 5, DB5 Bit 6, DB6 Bit 7, DB7 Backlight 5V (Vcc - Needs Resistor) Backlight Ground (Vss)

  
  
• and variable resistor will be connect as below.
  
  

I started begin learning how to interface LCD mudule and Arduino Board and can worked!. I found a good example from http://digital-salvage.net/?p=124 by David A. Mellis library modified 5 Jul 2009 by Limor Fried (http://www.ladyada.net) example added 9 Jul 2009 by Tom Igoe modified 25 July 2009 by David A. Mellis easy to my understand.

And We should do learn how to use LiquidCrystal.h library where there are a lot of function.
this is GOOD example ,below coding I already test. It 's worked.

/*
  LiquidCrystal Library - Hello World
 
 Demonstrates the use a 16x2 LCD display.  The LiquidCrystal
 library works with all LCD displays that are compatible with the 
 Hitachi HD44780 driver. There are many of them out there, and you
 can usually tell them by the 16-pin interface.
 
 This sketch prints "Hello World!" to the LCD
 and shows the time.
 
  The circuit:
 * LCD RS pin to digital pin 12
 * LCD Enable pin to digital pin 11
 * LCD D4 pin to digital pin 5
 * LCD D5 pin to digital pin 4
 * LCD D6 pin to digital pin 3
 * LCD D7 pin to digital pin 2
 * 10K resistor:
 * ends to +5V and ground
 * wiper to LCD VO pin (pin 3)
 
 Library originally added 18 Apr 2008
 by David A. Mellis
 library modified 5 Jul 2009
 by Limor Fried (http://www.ladyada.net)
 example added 9 Jul 2009
 by Tom Igoe
 modified 25 July 2009
 by David A. Mellis
 
 
 http://www.arduino.cc/en/Tutorial/LiquidCrystal
 */

// include the library code:
#include 

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {
  // set up the LCD's number of rows and columns: 
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.print("hello, world!");
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(0, 1);
  // print the number of seconds since reset:
  lcd.print(millis()/1000);
}