2011

Author: Manoj.j

Reviewer: Ram

Revision: 1.3

Tenet Technetronics

1/8/2011

LCD breakout user manual

i

Contents

Introduction

Introduction to LCD breakout

Hardware Overview

LCD breakout features

Components overview

Schematic

Software Overview

Flow Chart

Pseudo code

Code

Demo Application

References and further reading

2

Introduction

This breakout board is designed to simplify the physical connection in interfacing an LCD with an Arduino. The breakout board is compatible for both 16x2 character LCD and graphical LCD. All power and control pins necessary to connect it to the Arduino/Comet board are broken out using long wire-wrap headers which extend through the shield. The breakout can be reset through reset button on top of the breakout. Separate variable potentiometer is provided for both 16x2 character LCD and graphical LCD to control the backlight contrast.

Hardware Overview

Figure1: The LCD breakout

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LCD breakout features

The breakout supports both Graphical LCD and 16x2 Text LCD.

The LCD breakout shield can be mounted on Arduino/Comet board.

The backlight contrast can be adjusted through potentiometer.

Components overview

Table1: components overview

Components

Brief

specificatio

n

Product link

References

Potentiometer Resistance:

10 kilo ohm

http://tenettech.com/

product.php?id_pro

duct=1498

http://en.wikipedia.org/wiki/Potentiometer

Reset button Normal push

button

http://tenettech.com/

product.php?id_pro

duct=1499

http://en.wikipedia.org/wiki/Push-button

Extended LCD

berg

connectors

16x2 LCD http://tenettech.com/

product.php?id_pro

duct=517

http://en.wikipedia.org/wiki/Liquid_crystal_dis

play

Graphical LCD 128x64 LCD http://www.tenettech.com/product.php?id_product=1523

http://www.dfrobot.com/wiki/index.php?title=128x64_Graphic_LCD_%28SKU:FIT0021%29

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Schematic

Figure 2: 16x2 text LCD and graphical LCD breakout schematic

5

Software overview

Flowchart

16x2LCD Graphical LCD

Initialization of LCD

functional pins

Set the (cursor, clear

screen) status

Print statements to

display

Start

End

Initialization of LCD

functional pins

Initialization of

bitmap

position/system font

Add shapes

to images

Initialization of LCD

functional pins

Set the (cursor, clear

screen) status

Print statements to

display

Start

End

Start

End

Print

6

Pseudo code

16x2LCD

Include header files for LCD

Global declaration: LCD pins initialization.

Function name : Setup

Return type : Void

Description : Initialization

Body : Print statement that is to be displayed on LCD.

Function name : Loop

Return type : Void

Description : Infinite

Body : Set the cursor and rate at which it is to be displayed.

Graphical LCD

Include header files for LCD

Function name : Setup

Return type : Void

Description : Initialization

Body : LCD pins initialization.

Set up the Bitmap position

Set the system font

Function name : Loop

Return type : Void

Description : Infinite

Body : Include the shapes which you need to add to images

Include number of iterations in one second.

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code

(i) 16x2 LCD

// 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);

}

(ii) Graphical LCD

#include <ks0108.h> // library header

#include <Arial14.h> // font definition for 14 point Arial font.

#include "SystemFont5x7.h" // system font

#include "ArduinoIcon.h" // bitmap

unsigned long startMillis;

unsigned int iter = 0;

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void setup()

{

GLCD.Init(NON_INVERTED); // initialise the library

GLCD.ClearScreen();

GLCD.DrawBitmap(ArduinoIcon, 32,0, BLACK); //draw the bitmap at the given x,y position

delay(3000);

GLCD.ClearScreen();

GLCD.SelectFont(System5x7); // select fixed width system font

}

void loop()

{ // run over and over again

startMillis = millis();

while( millis() - startMillis < 1000)

{ // loop for one second

GLCD.DrawRect(0, 0, 64, 61, BLACK); // rectangle in left side of screen

GLCD.DrawRoundRect(68, 0, 58, 61, 5, BLACK); // rounded rectangle around text area

for(int i=0; i < 62; i += 4)

GLCD.DrawLine(1,1,63,i, BLACK); // draw lines from upper left down right side of

rectangle

GLCD.DrawCircle(32,31,30,BLACK); // draw circle centered in the left side of screen

GLCD.FillRect(92,40,16,16, WHITE); // clear previous spinner position

GLCD.CursorTo(5,5); // locate curser for printing text

GLCD.PrintNumber(++iter); // print current iteration at the current cursor position

}

// display number of iterations in one second

GLCD.ClearScreen(); // clear the screen

GLCD.CursorTo(13,2); // positon cursor

GLCD.Puts("FPS= "); // print a text string

GLCD.PrintNumber(iter); // print a number

}

9

Demo Application

LCD breakout shield

Figure3: The breakout

LCD shield is mounted on Comet through extended headers from the breakout

Figure4: The breakout with Comet

16x2 text LCD is connected to breakout

Figure5: The breakout with LCD

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The result image shows characters are printed on LCD

Figure6: character displayed on LCD

Graphical LCD is interfaced to Comet using the breakout shield

Figure7: The breakout with graphical LCD

The result showing coded images in graphical LCD

Figure8: images displayed on graphical LCD

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References and Further Reading

www.arduino.cc

www.tenettech.com/comet

http://www.youtube.com/user/tenetworld?blend=2&ob=5#p/u/3/NJHPJblpkRU

http://tenettech.com/category.php?id_category=283