avr_piano/lcd.c

#include <avr/io.h>    //standard AVR header

#define F_CPU 16000000UL	// THE CPU FREQUENCY 
#include <util/delay.h>		//delay header

#define	LCD_DPRT	PORTD 	//LCD DATA PORT	
#define	LCD_DDDR	DDRD	//LCD DATA DDR
#define	LCD_DPIN	PIND	//LCD DATA PIN
#define	LCD_CPRT	PORTB	//LCD COMMANDS PORT
#define	LCD_CDDR	DDRB	//LCD COMMANDS DDR
#define	LCD_CPIN	PINB	//LCD COMMANDS PIN
#define	LCD_RS  0		//LCD RS
#define	LCD_EN  1		//LCD EN

void lcd_putValue(unsigned char val){
	LCD_DPRT &= 0x0F;
	LCD_DPRT |= (val&0xF0);		//send cmnd to data port
	LCD_CPRT |= (1<<LCD_EN);		//EN = 1 for H-to-L pulse
	_delay_us(1);				//wait to make enable wide
	LCD_CPRT &= ~ (1<<LCD_EN);	//EN = 0 for H-to-L pulse
	_delay_us(100);			//wait to make enable wide

	LCD_DPRT &= 0x0F;
	LCD_DPRT |= val<<4;			//send cmnd to data port
	LCD_CPRT |= (1<<LCD_EN);		//EN = 1 for H-to-L pulse
	_delay_us(1);				//wait to make enable wide
	LCD_CPRT &= ~ (1<<LCD_EN);	//EN = 0 for H-to-L pulse
	_delay_us(100);			//wait to make enable wide  	
}

//*******************************************************
void lcdCommand( unsigned char cmnd ){	
	LCD_CPRT &= ~ (1<<LCD_RS);		//RS = 0 for command	
	lcd_putValue(cmnd);
}

//*******************************************************
void lcdData( unsigned char data )
{
	LCD_CPRT |= (1<<LCD_RS);		//RS = 1 for data 	
	lcd_putValue(data);	 
}

void lcd_clear()
{
	lcdCommand(0x01);	
	_delay_us(1700);
}

void lcd_showCursor()
{
	lcdCommand(0x0E);
	_delay_us(50);
}

void lcd_hideCursor()
{
	lcdCommand(0x0C);
	_delay_us(50);
}

//*******************************************************
void lcd_init()
{
	LCD_DDDR |= 0xF0;
	LCD_CDDR |= (1<<LCD_RS)|(1<<LCD_EN);
 
	LCD_CPRT &=~(1<<LCD_EN);	//LCD_EN = 0
	_delay_us(2000);	//wait for init.

	lcdCommand(0x33);	//send $33 for init.
	lcdCommand(0x32);	//send $32 for init
	lcdCommand(0x28);	//init. LCD 2 line,5*7 matrix
	lcdCommand(0x0e);	//display on, cursor on
	lcdCommand(0x06);	//shift cursor right

	lcd_clear();		
}

//*******************************************************
void lcd_gotoxy(unsigned char x, unsigned char y)
{  
	unsigned char firstCharAdr[]={0x80,0xC0,0x94,0xD4};//Table 12-4  
	lcdCommand(firstCharAdr[y-1] + x - 1);
	_delay_us(100);	
}

//*******************************************************
void lcd_print( char * str )
{
	unsigned char i = 0;

	while(str[i] != 0) //while it is not end of string
	{
		lcdData(str[i]);
		i++ ;
	}
}

//*******************************************************
int main(void) 
{	
	lcd_init();
	lcd_hideCursor();
	
	while(1)
	{	
		lcd_clear();
		lcd_gotoxy(1,1);
		lcd_print("The world is but");
		lcd_gotoxy(1,2);
		lcd_print("one country");

		lcd_showCursor();
		_delay_ms(2500);
	
		lcd_clear();
	
		lcd_gotoxy(1,1);
		lcd_print("and mankind its");
		lcd_gotoxy(1,2);
		lcd_print("citizens.");	
		_delay_ms(3500);	
	}

	return 0;
}