This week we are going to show how simple it is use an LCD with an Arduino. We will use the LCD in future episodes to output information from Sensors and for debugging other applications.
We will give you a schematic so you can quickly connect an LCD to your Arduino. You will learn how to scroll text, blink text and much more.
Downloads
Schematic
Sample Code
Hello World
/*
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
* LCD R/W pin to ground
* 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 22 Nov 2010
by Tom Igoe
This example code is in the public domain.
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, 5, 4, 3, 2);
void setup() {
// set up the LCD's number of columns and rows:
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);
}
Display (on and off)
/*
LiquidCrystal Library - display() and noDisplay()
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 uses the
display() and noDisplay() functions to turn on and off
the display.
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
* LCD R/W pin to ground
* 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 22 Nov 2010
by Tom Igoe
This example code is in the public domain.
http://arduino.cc/en/Tutorial/LiquidCrystalDisplay
*/
// include the library code:
#include <LiquidCrystal.h>
// 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 columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print("hello, world!");
}
void loop() {
// Turn off the display:
lcd.noDisplay();
delay(500);
// Turn on the display:
lcd.display();
delay(500);
}
Blink
/*
LiquidCrystal Library - Blink
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 makes the
cursor block blink.
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
* LCD R/W pin to ground
* 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 22 Nov 2010
by Tom Igoe
This example code is in the public domain.
http://arduino.cc/en/Tutorial/LiquidCrystalBlink
*/
// include the library code:
#include <LiquidCrystal.h>
// 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 columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print("hello, world!");
}
void loop() {
// Turn off the blinking cursor:
lcd.noBlink();
delay(3000);
// Turn on the blinking cursor:
lcd.blink();
delay(3000);
}
Text Direction
/*
LiquidCrystal Library - TextDirection
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 demonstrates how to use leftToRight() and rightToLeft()
to move the cursor.
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
* LCD R/W pin to ground
* 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 22 Nov 2010
by Tom Igoe
This example code is in the public domain.
http://arduino.cc/en/Tutorial/LiquidCrystalTextDirection
*/
// include the library code:
#include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
int thisChar = 'a';
void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// turn on the cursor:
lcd.cursor();
}
void loop() {
// reverse directions at 'm':
if (thisChar == 'm') {
// go right for the next letter
lcd.rightToLeft();
}
// reverse again at 's':
if (thisChar == 's') {
// go left for the next letter
lcd.leftToRight();
}
// reset at 'z':
if (thisChar > 'z') {
// go to (0,0):
lcd.home();
// start again at 0
thisChar = 'a';
}
// print the character
lcd.write(thisChar);
// wait a second:
delay(1000);
// increment the letter:
thisChar++;
}
Auto Scroll
/*
LiquidCrystal Library - Autoscroll
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 demonstrates the use of the autoscroll()
and noAutoscroll() functions to make new text scroll or not.
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
* LCD R/W pin to ground
* 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 22 Nov 2010
by Tom Igoe
This example code is in the public domain.
http://arduino.cc/en/Tutorial/LiquidCrystalAutoscroll
*/
// include the library code:
#include <LiquidCrystal.h>
// 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 columns and rows:
lcd.begin(16,2);
}
void loop() {
// set the cursor to (0,0):
lcd.setCursor(0, 0);
// print from 0 to 9:
for (int thisChar = 0; thisChar < 10; thisChar++) {
lcd.print(thisChar);
delay(500);
}
// set the cursor to (16,1):
lcd.setCursor(16,1);
// set the display to automatically scroll:
lcd.autoscroll();
// print from 0 to 9:
for (int thisChar = 0; thisChar < 10; thisChar++) {
lcd.print(thisChar);
delay(500);
}
// turn off automatic scrolling
lcd.noAutoscroll();
// clear screen for the next loop:
lcd.clear();
}
Scroll (Left and Right)
/*
LiquidCrystal Library - scrollDisplayLeft() and scrollDisplayRight()
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 uses the
scrollDisplayLeft() and scrollDisplayRight() methods to scroll
the text.
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
* LCD R/W pin to ground
* 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 22 Nov 2010
by Tom Igoe
This example code is in the public domain.
http://arduino.cc/en/Tutorial/LiquidCrystalScroll
*/
// include the library code:
#include <LiquidCrystal.h>
// 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 columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print("hello, world!");
delay(1000);
}
void loop() {
// scroll 13 positions (string length) to the left
// to move it offscreen left:
for (int positionCounter = 0; positionCounter < 13; positionCounter++) {
// scroll one position left:
lcd.scrollDisplayLeft();
// wait a bit:
delay(150);
}
// scroll 29 positions (string length + display length) to the right
// to move it offscreen right:
for (int positionCounter = 0; positionCounter < 29; positionCounter++) {
// scroll one position right:
lcd.scrollDisplayRight();
// wait a bit:
delay(150);
}
// scroll 16 positions (display length + string length) to the left
// to move it back to center:
for (int positionCounter = 0; positionCounter < 16; positionCounter++) {
// scroll one position left:
lcd.scrollDisplayLeft();
// wait a bit:
delay(150);
}
// delay at the end of the full loop:
delay(1000);
}