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LiquidCrystal - autoscroll()

The Liquid Crystal 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 shows how to use the autoscroll() and noAutoscroll() methods to move all the text on the display left or right.

autoscroll() moves all the text one space to the left each time a letter is added

noAutoscroll() turns scrolling off

This sketch prints the characters 0 to 9 with autoscroll off, then moves the cursor to the bottom right, turns autoscroll on, and prints them again.

Hardware Required

  • Arduino Board
  • LCD Screen (compatible with Hitachi HD44780 driver)
  • pin headers to solder to the LCD display pins
  • 10k Potentiometer
  • breadboard
  • hook-up wire

Circuit

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.
To wire your LCD 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 the LCD screen's VO pin (pin3).

click the images to enlarge

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

Code

/*
  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();
}

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