#define F_CPU 16000000UL
#include <avr/io.h>
#include <util/delay.h>
#include <string.h>
#include <math.h>
#include <stdio.h>

#define LCD_Port PORTD
#define LCD_DPin DDRD
#define RS PD2
#define EN PD3

void LCD_Action( unsigned char cmnd );
void LCD_Init (void);
void LCD_Clear();
void LCD_Print (const char *str);
void LCD_Pos (char row, char pos, char *str);
float x = 0;
unsigned char xchar; 

void LCD_Init (void)
{
	LCD_DPin = 0xFF;	//Control LCD Pins (D4-D7)
	_delay_ms(15);		//Wait before LCD activation
	LCD_Action(0x02);	//4-Bit Control
	LCD_Action(0x28);       //Control Matrix @ 4-Bit
	LCD_Action(0x0c);       //Disable Cursor
	LCD_Action(0x06);       //Move Cursor
	LCD_Action(0x01);       //Clean LCD
	_delay_ms(2);
}

void LCD_Action( unsigned char cmnd )
{
	LCD_Port = (LCD_Port & 0x0F) | (cmnd & 0xF0);
	LCD_Port &= ~ (1<<RS);
	LCD_Port |= (1<<EN);
	_delay_us(1);
	LCD_Port &= ~ (1<<EN);
	_delay_us(200);
	LCD_Port = (LCD_Port & 0x0F) | (cmnd << 4);
	LCD_Port |= (1<<EN);
	_delay_us(1);
	LCD_Port &= ~ (1<<EN);
	_delay_ms(2);
}

void LCD_Clear()
{
	LCD_Action (0x01);		//Clear LCD
	_delay_ms(2);			//Wait to clean LCD
	LCD_Action (0x80);		//Move to Position Line 1, Position 1
}

void LCD_Print (const char *str)
{
	int i;
	for(i=0; str[i]!=0; i++)
	{
		LCD_Port = (LCD_Port & 0x0F) | (str[i] & 0xF0);
		LCD_Port |= (1<<RS);
		LCD_Port|= (1<<EN);
		_delay_us(1);
		LCD_Port &= ~ (1<<EN);
		_delay_us(200);
		LCD_Port = (LCD_Port & 0x0F) | (str[i] << 4);
		LCD_Port |= (1<<EN);
		_delay_us(1);
		LCD_Port &= ~ (1<<EN);
		_delay_ms(2);
	}
}

int main()
{
  float n;
	LCD_Clear();
	LCD_Init();
	LCD_Print(" Voltaje: ");	//Begin writing at Line 1, Position 1
	DDRC = 0; //make Port C an input for ADC input
	ADCSRA= 0x8F; //enable and interrupt select ck/128
	ADMUX= 0x40; //2.56V Vref and ADC0 single-ended
	//input right-justified data
	ADCSRA|=(1<<ADSC); //start conversion
	
	while (1){
    ADCSRA|=(1<<ADSC); //start conversion
    while((ADCSRA&(1<<ADIF))==0);//wait for conversion to finish
    //LCD_Clear();
    n = ADC&1023; 
    LCD_Action (0x80);
    LCD_Print(" Voltaje: ");
    x =n*0.00488;
    char string[]="";
    //LCD_Action (0xC0); //Jump next line
    sprintf(string, "%d", (int)x); //Entero
    LCD_Print(string);
    sprintf(string, ".");
    LCD_Print(string);
    sprintf(string, "%d", ((int)(x*100)%100)); //Decimal
    LCD_Print(string);
		LCD_Print(" V ");
  }
}