Notes

#include <avr/io.h>
#include <util/delay.h>
#include <string.h>

#define LCD_PORT PORTB
#define LCD_DDR DDRB
#define RS 0
#define EN 1
#define DB4 4
#define DB5 5
#define DB6 6
#define DB7 7

int main(void)
{
LCD_DDR = (0xF0) | (_BV(RS)) | (_BV(EN));
_delay_ms(20);

LCD_Init();

LCD_String("Bartek Skorek");
LCD_Command(0xC0);
LCD_String("5.5/10");

while(1) {}
}

void LCD_Init()
{
LCD_Command(0x33);
LCD_Command(0x32); /* Send for 4 bit initialization of LCD */
LCD_Command(0x28); /* 2 line, 5*7 matrix in 4-bit mode */
LCD_Command(0x0c); /* Display on cursor off */
LCD_Command(0x06); /* Increment cursor (shift cursor to right) */
LCD_Command(0x01); /* Clear display screen */
}

void LCD_String (char *str) /* Send string to LCD function */
{
int i;
for(i=0;str[i]!=0;i++) /* Send each char of string till the NULL */
{
LCD_Char (str[i]);
}
}

void LCD_Command( unsigned char cmnd )
{
LCD_PORT = (LCD_PORT & 0x0F) | (cmnd & 0xF0);/* Sending upper nibble */
LCD_PORT &= ~ (1<<RS); /* RS=0, command reg. */
LCD_PORT |= (1<<EN); /* Enable pulse */
_delay_us(1);
LCD_PORT &= ~ (1<<EN);
_delay_us(200);
LCD_PORT = (LCD_PORT & 0x0F) | (cmnd << 4);/* Sending lower nibble */
LCD_PORT |= (1<<EN);
_delay_us(1);
LCD_PORT &= ~ (1<<EN);
_delay_ms(2);
}

void LCD_Char( unsigned char data )
{
LCD_PORT = (LCD_PORT & 0x0F) | (data & 0xF0);/* Sending upper nibble */
LCD_PORT |= (1<<RS); /* RS=1, data reg. */
LCD_PORT|= (1<<EN);
_delay_us(1);
LCD_PORT &= ~ (1<<EN);
_delay_us(200);
LCD_PORT = (LCD_PORT & 0x0F) | (data << 4); /* Sending lower nibble */
LCD_PORT |= (1<<EN);
_delay_us(1);
LCD_PORT &= ~ (1<<EN);
_delay_ms(2);
}