LCD THEORY & WORKING PRINCIPLES

USE LCD WITH AVR

• LCD - Liquid Crystal Display• Mostly used for Display of Message• Highly user interactive

Robo Indiahttp://roboindia.com

LCD

• We are using 16x2 character LCD• 16x2 LCD means max 16 characters per

line can be displayed and there are 2 lines

• Single character is displayed in 5x7 pixel matrix

LCD SCHEMATIC

LCD SCHEMATIC

• RS – To any pin of your choice• RW – To any pin of your choice• E – To any pin of your choice• D0….D3 – Not Connected• D4….D7 – PINX,0 …. PINX,3• D4 must be connected to PIN0 of X PORT :• D7 must be connected to PIN3 of X PORT

CONNECTIONS

• RS – To any pin of your choice• RW – To any pin of your choice• E – To any pin of your choice• D0….D3 – Not Connected• D4….D7 – PINX,0 …. PINX,3• D4 must be connected to PIN0 of X PORT :• D7 must be connected to PIN3 of X PORT

CONNECTIONS

• RS – Reset• RW – Rewrite• E – Enable• D3 …. D7 – Data Line• Anode - +5V • Cathode - GND

PIN DESCRIPTION

ADDING HEADER FILE

• #define LCD_DATA C //Port PC0-PC3 are connected to D4-D7

• #define LCD_E C //Enable signal• #define LCD_E_POS PC5 //Position of enable in above port

• #define LCD_RS C• #define LCD_RS_POS PC7

• #define LCD_RW C• #define LCD_RW_POS PC6

HEADER FILE HANDLING

INITIALIZING LCD

InitLCD(LS_BLINK); //initialize LCD

• Above command will initialize the LCD

FUNCTIONS OF HEADER

CLEAR LCD

LCDClear(); // To clear the display

• Above command will CLEAR the LCD

FUNCTIONS OF HEADER

DISPLAY TEXT ON LCD

LCDWriteStringXY(X,Y,“Message");

• Above command Write the text on LCD • X,Y are coordinates• X = 0 …. 15• Y = 0 and 1

FUNCTIONS OF HEADER

DISPLAY VARIABLE ON LCD

LCDWriteInt(X,Y,variable,field length);

• Above command Write the variable on LCD• X,Y define position of coordinates• X = 0 …. 15• Y = 0 and 1• Variable = variable which we print • Field length = Num of Decimal places

FUNCTIONS OF HEADER

DISPLAY VARIABLE ON LCD

LCDWriteInt(X,Y,variable,field length);

• Above command Write the variable on LCD• X,Y define position of coordinates• X = 0 …. 15• Y = 0 and 1• Variable = variable which we print • Field length = Num of Decimal places

FUNCTIONS OF HEADER

In case of queries please write us-

info@roboindia.com

THANKS