/*#define D4 PORTD0
#define D5 PORTD1
#define D6 PORTD2
#define D7 PORTD3*/

#define F_CPU 8000000UL	   //Define CPU Frequency e.g. here 8MHz 
#include <avr/io.h>		     //Include AVR std. library file 
#include <util/delay.h>		 // Include Delay header file 

#define LCD_Dir  DDRB		   //Define LCD data port direction 
#define LCD_Port PORTB		// Define LCD data port
#define RS PB0			/* Define Register Select pin */
#define EN PB1 			/* Define Enable signal pin */

void LCD_Command( unsigned char cmnd )
{
	LCD_Port = (LCD_Port & 0x0F) | (cmnd & 0xF0);     /* Sending upper nibble of the command*/
	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 of the cpmmand*/
	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);
}

void LCD_Init (void)			/* LCD Initialize function */
{
	LCD_Dir = 0xFF;			/* Make LCD port direction as o/p */
	_delay_ms(20);			/* LCD Power ON delay always >15ms */
	
	LCD_Command(0x02);		/* 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*/
	_delay_ms(2);
}

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]);
    _delay_ms(2);
	}
}

void LCD_string(char *s, int LCD_line, int LCD_cursor_position)
{
	if (LCD_line == 1)
	LCD_Command(0x80 + LCD_cursor_position);
	else
	LCD_Command(0xc0 + LCD_cursor_position);
	while (*s)
	LCD_Char(*s++); // ++ is equivalent to increment
}

void LCD_cursor_blink(void)	//displays LCD blinking cursor
{
	LCD_Command(0x0F);
}

void LCD_string_Float(float LCD_number, int LCD_line, int LCD_cursor_position)
{
	char buffer_LCD[13];

	dtostre(LCD_number, buffer_LCD, 5, 4);
	LCD_string(buffer_LCD, LCD_line, LCD_cursor_position);
}

void LCD_string_Int(int LCD_number, int LCD_line, int LCD_cursor_position)
{
	char buffer_LCD[10];
	
	itoa(LCD_number, buffer_LCD, 10);
	LCD_string(buffer_LCD, LCD_line, LCD_cursor_position);
}


void LCD_Clear()
{
	LCD_Command (0x01);		/* Clear display */
	_delay_ms(2);
	LCD_Command (0x80);		/* Cursor at home position */
}


void LCD_ShiftLeft(void)
{
  /*for(int i=0;i<LCD_Char;i++)
  {
      LCD_Command(0x18);
      _delay_ms(100);
  }*/
  int i=0;
  while(i<LCD_String){
    i++;
    LCD_Command(0x18);
    _delay_ms(100);
  }
}
void LCD_ShiftRight(void)
{
  int i=0;
  for(int i=0;i<LCD_String;i++)
  {
      LCD_Command(0x1c);
      _delay_ms(100);
  }
}

int LCD_lencount(){
  int len =0;
  for(int i=0;i<LCD_String;i++){
    len = len + 1;
  }
  return len;
}


int main()
{
	LCD_Init();			/* Initialization of LCD*/

	/*LCD_String("ECE Microcontroller");	
  // Write string on 1st line of LCD
	LCD_Command(0xC0);		//Go to 2nd line
	LCD_String("4-bit Mode");	// Write string on 2nd line
  LCD_ShiftLeft();_delay_ms(10);LCD_Clear();*/

  /*LCD_String("ECE Microcontroller");	
  // Write string on 1st line of LCD
	LCD_Command(0xC0);		// Go to 2nd line
	LCD_String("4-bit Mode");	// Write string on 2nd line
  LCD_ShiftRight();_delay_ms(10);LCD_Clear();*/
  
	while(1);
}