Before wiring the LCD screen to your Arduino we suggest to solder a pin header strip to the 14 (or 16) pin count connector of the LCD screen, as you can see in the image above.\\

• pin headers to solder to the LCD display pins

Before wiring the LCD screen to your Arduino we suggest you to solder a pin headers strip to the LCD screen, as you can see in the image above.

To wire your LCD screen to your Arduino, connect the following pins:

(:source http://arduino.cc/en/pub/code/master/libraries/LiquidCrystal/examples/HelloWorld/HelloWorld.ino lang=arduino tabwidth=4:)

LiquidCrystal - "Hello World!"

LiquidCrystal

• Liquid Crystal Library

<<<<<<<

• [[Reference/LiquidCrystal | Liquid Crystal Library]

The process of controlling the display involves putting the data that form the image of what you want to display into the data registers, then putting instructions in the instruction register. The LiquidCrystal Library simplifies this for you so you don't need to know the low-level instructions.

• lcd.begin()
• lcd.print()
• lcd.setCursor()

The process of controlling the display involves putting the data that form the image of what you want to display into the data registers, then putting instructions in the instruction register. The LiquidCrystal library simplifies this for you so you don't need to know the low-level instructions.

source http://arduino.cc/en/pub/code/master/libraries/LiquidCrystal/examples/HelloWorld/HelloWorld.pde lang=arduino tabwidth=4

)

(:source http://arduino.cc/en/pub/code/master/libraries/LiquidCrystal/examples/HelloWorld/HelloWorld.pde lang=arduino tabwidth=4:)

To wire your LED screen to your Arduino, connect the following pins:

• 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

Additionally, wire a 10K pot to +5V and GND, with it's wiper (output) to LCD screens VO pin (pin3).

click the images to enlarge

(:div class=circuit :)

• LCD Screen (compatible with Hitachi HD44780 driver)
• 10k Potentiometer
• breadboard
• hook-up wire

div class=circuit

)

click the image to enlarge

(:div class=BOM :)

Hardware Required

• Arduino Board

Circuit

(:div class=circuit :) There is no circuit for this example.

image developed using Fritzing. For more circuit examples, see the Fritzing project page

(:divend:)

Code

(:div class=code :)

(:source http://arduino.cc/en/pub/code/master/libraries/LiquidCrystal/examples/HelloWorld/HelloWorld.pde lang=arduino tabwidth=4:)

(:divend:)

Code

(:divend:)

See Also:

• Blink: control of the block-style cursor.
• Cursor: control of the underscore-style cursor.
• Display: quickly blank the display without losing what's on it.
• TextDirection: control which way text flows from the cursor.
• Scroll: scroll text left and right.
• Serial input: accepts serial input, displays it.
• SetCursor: set the cursor position.
• Autoscroll: shift text right and left.

(:source http://arduino.cc/en/pub/code/master/libraries/LiquidCrystal/examples/HelloWorld/HelloWorld.pde lang=arduino tabwidth=4:)

   LiquidCrystal Library - setCursor

  This sketch prints to all the positions of the LCD using the
  setCursor(0 method:

  The circuit:

  by Tom Igoe 
  modified 22 August 2009

 // these constants won't change.  But you can change the size of
 // your LCD using them:
 const int numRows = 2;
 const int numCols = 16;

   lcd.begin(numRows, numCols);

   // loop from ASCII 'a' to ASCII 'z':
   for (int thisLetter = 'a'; thisLetter <= 'z'; thisLetter++) {
     // loop over the rows:
     for (int thisRow= 0; thisRow < numRows; thisRow++) {
       // loop over the columns:
       for (int thisCol = 0; thisCol < numCols; thisCol++) {
         // set the cursor position:
         lcd.setCursor(thisCol,thisRow);
         // print the letter:
         lcd.print(thisLetter, BYTE);
         delay(200);
       }
     }
   }

   LiquidCrystal Library - Hello World

  This sketch prints "Hello World!" to the LCD
  and shows the time.

  by Tom Igoe
  modified 25 July 2009
  by David A. Mellis

 #include <LiquidCrystal.h>

 LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

   lcd.begin(16, 2);

   // 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);
 }

The process of controlling the display involves putting the data that form the image of what you want to display into the data registers, then putting instructions in the instruction register. The LiquidCrystal library simplifies this for you so you don't need to know the low-level instructions.

   LiquidCrystal Library - scrollDisplayLeft() and scrollDisplayRight()

  This sketch prints "Hello World!" to the LCD and uses the
  scrollDisplayLeft() and scrollDisplayRight() methods to scroll
  the text.

   The circuit:

  * LCD Enable pin to digital pin 11

  by Limor Fried (http://www.ladyada.net)
  example added 9 Jul 2009

 LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

   // set up the LCD's number of rows and columns: 

   lcd.setCursor(0,7);

   // scroll 27 positions (display length + string length) to the left:
   for (int positionCounter = 0; positionCounter < 27; positionCounter++) {
     // scroll one position left:
     lcd.scrollDisplayLeft(); 
     // wait a bit:
     delay(200);
   }

   // scroll 27 positions (display length + string length) to the right:
   for (int positionCounter = 0; positionCounter < 27; positionCounter++) {
     // scroll one position right:
     lcd.scrollDisplayRight(); 
     // wait a bit:
     delay(200);
   }
 }

(:include LiquidCrystalCircuit :)

• LCD enable pin connected to digital I/O pin 10

Other LiquidCrystal Library Examples

• HelloWorld - displays "hello world!" and the seconds since reset

• Serial input - accepts serial input, displays it

Other LiquidCrystal Library Examples

• HelloWorld
• Blink
• Cursor
• Display
• IncrementDecrement
• Scroll
• LiquidCrystalSerial - accepts serial input, displays it
• SetCursor
• Shift

There's also a display constrast pin (Vo), power supply pins (+5V and Gnd) and LED Backlight (Bklt+ and BKlt-) pins that you can use to power the LCD, control the display contrast, and turn on and off the LED backlight, respectively.

The LCDs have a parallel interface, meaning that the microcontroller has to manipulate several interface pins at once to control the display. The interface consists of the following pins:

A register select (RS) pin that controls where in the LCD's memory you're writing data to. You can select either the data register, which holds what goes on the screen, or an instruction register, which is where the LCD's controller looks for instructions on what to do next.

A Read/Write (R/W) pin that selects reading mode or writing mode

An Enable pin that enables writing to the registers

8 data pins (D0 -D7). The states of these pins (high or low) are the bits that you're writing to a register when you write, or the values you're reading when you read.

The process of controlling the display involves putting the bitmap of what you want to display into the data registers,then putting instructions in the instruction register. The LiquidCrystal simplifies this for you so you don't need to know the low-level instructions.

NOTE: The LiquidCrystal library has undergone revisions after Arduino version 0016. Thanks to Limor Fried for the rewrite to include 4-bit and 8-bit modes and more functionality. If you are running Arduino 0016 or earlier, please download the current version of the LiquidCrystal library and install it in your hardware/libraries folder.

output of the sketch on a 2x16 LCD

NOTE: The LiquidCrystal library has undergone revisions after Arduino version 0016. Thanks to Limor Fried for the rewrite to include 4-bit and 8-bit modes and more functionality. If you are running Arduino 0016 or earlier, please download the current version of the LiquidCrystal library? and install it in your hardware/libraries folder.

NOTE: The LiquidCrystal library has undergone revisions after Arduino version 0016. If you are running Arduino 0016 or earlier, please download the current version of the LiquidCrystal library? and install it in your hardware/libraries folder.

Users of 0017 and later will not need to install the update.

(:div class=code :)

 /*
   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 R/W pin to digital pin 11
  * LCD Enable pin to digital pin 10
  * 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
  example added 7 Jul 2009
  by Tom Igoe 
  
  http://www.arduino.cc/en/Tutorial/LiquidCrystal
  */

 // include the library code:
 #include <LiquidCrystal.h>

 // initialize the library with the numbers of the interface pins
 LiquidCrystal lcd(12, 11, 10, 5, 4, 3, 2);

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

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

(:divend:)

Examples > Libraries > LiquidCrystal

LiquidCrystal

The LiquidCrystal library allows you to control 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 example sketch prints "Hello World!" to the LCD and shows the time in seconds since the Arduino was reset.

The Hitachi-compatible LCDs can be controlled in two modes: 4-bit or 8-bit. The 4-bit mode requires seven I/O pins from the Arduino, while the 8-bit mode requires 11 pins. For displaying text on the screen, you can do most everything in 4-bit mode, so example shows how to control a 2x16 LCD in 4-bit mode.

Circuit

• LCD RS pin connected to digital I/O pin 12
• LCD R/W pin connected to digital I/O pin 11
• LCD enavle pin connected to digital I/O pin 10
• LCD pins D0 - D3 connected to digital I/O pins 2 through 5, respectively
• LCD voltage and ground connected to +5V and ground
• LCD Vo pin, which controls the contrast, connected to a potentiometer. Adjust the potentiometer to get the text to display at the contrast ratio you want.

click the image to enlarge

Schematic:

click the image to enlarge

Code