LCD Interfacing WinAVR Routines

July 25, 2009 by admin
Filed under: Uncategorized

Circuit Diagram For LCD interface

LCD.H


#define lcd_port   PORTB

//LCD Registers addresses
#define LCD_RS      0×01
#define LCD_RW     0×02
#define LCD_EN      0×08

void lcd_reset(void)
{
lcd_port = 0xFF;
_delay_ms(20);
lcd_port = 0×30+LCD_EN;
lcd_port = 0×30;
_delay_ms(10);
lcd_port = 0×30+LCD_EN;
lcd_port = 0×30;
_delay_ms(1);
lcd_port = 0×30+LCD_EN;
lcd_port = 0×30;
_delay_ms(1);
lcd_port = 0×20+LCD_EN;
lcd_port = 0×20;
_delay_ms(1);
}
void lcd_cmd (char cmd)
{
lcd_port = (cmd & 0xF0)|LCD_EN;
lcd_port = (cmd & 0xF0);
lcd_port = ((cmd << 4) & 0xF0)|LCD_EN;
lcd_port = ((cmd << 4) & 0xF0);
_delay_ms(2);
_delay_ms(2);
}

void lcd_init (void)
{
lcd_reset();         // Call LCD reset
lcd_cmd(0×28);       // 4-bit mode – 2 line – 5×7 font.
lcd_cmd(0×0C);       // Display no cursor – no blink.
lcd_cmd(0×06);       // Automatic Increment – No Display shift.
lcd_cmd(0×80);       // Address DDRAM with 0 offset 80h.
}

void lcd_data (unsigned char dat)
{
lcd_port = ((dat & 0xF0)|LCD_EN|LCD_RS);
lcd_port = ((dat & 0xF0)|LCD_RS);
lcd_port = (((dat << 4) & 0xF0)|LCD_EN|LCD_RS);
lcd_port = (((dat << 4) & 0xF0)|LCD_RS);
_delay_ms(2);
_delay_ms(2);
}
void lcd_puts(char *aaa)
{
unsigned int i;
for(i=0;aaa[i]!=0;i++)
lcd_data(aaa[i]);
}
MAIN.C

#include<avr/io.h>                    //HEADER FILE FOR AVR INPUT OUTPUT
#include<compat/deprecated.h>//HEADER FILE FOR FUNCTIONS LIKE SBI
#include<util/delay.h>
#include<lcd.h>
/*—————————————————————-
—————–MAIN PROGRAM——-q——————————
—————————————————————–*/
int main(void)
{
//SET 1 for OUTPUT PORT
DDRB=0xFF;                                //SET 0 FOR INPUT PORT
PORTB=0×00;
lcd_init();
lcd_puts(”Devesh LCD demo”);
lcd_cmd(0xc0);
lcd_puts(”electroons.com”);

while(1)
{;
}
return 0;
}