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#include <stdio.h>
#include "lcd4.h"
#include "io_atmega16.h"


void  wait_milliseconds(int);


/*=== main ==============================================

  Programmet läser av en potentiometer som är ansluten till den
  analoga ingången kanal 0. Värdet skrivs sedan ut på en LCD display.

  ========================================================*/
 
int main(void)
{
    lcd4 theDisplay; //Structure variable
    char s[20];
    int value;
    double voltage;
    
    // Init of the LCD-display
    lcd4_init(&theDisplay,&PORTC,&DDRC,4000,50);
    
    // Init of the ADC
    ADCSRA = (ADCSRA & 0xF8) ;  //Prescale factor for the A/D
    ADCSRA = ADCSRA | (1<<ADEN); //Enable of the  A/D
  
    while ( 1 )
    { 
    
        // 1. READ OF THE ANALOG INPUT CHANNEL 0
        ADMUX = (ADMUX & 0xE0) | 0; // Analog input channel 0 
        ADCSRA = ADCSRA | (1<<ADSC); //A/D start of conversion
            
        while ( (ADCSRA & (1<<ADSC)) != 0 ) //Wait until conversion is done
            ;
            
        value = (unsigned int) ADC; //10 bits value, max value 1023 and min value 0
        
        // 2. CONVERSION OF THE 10 BITS VALUE (int) TO VOLTAGE VALUE (float) 
        voltage = 5.0*(value / 1023.0);
    
        // 3. WRITE OF THE VOLTAGE VALUE ON THE LCD-DISPLAY
        sprintf( s, "%2.1fV", voltage );
        lcd4_cup_row1(&theDisplay);
        lcd4_write_string( &theDisplay, s );
    }

  return 0;
}