adc.c

#ifndef F_CPU
# define F_CPU 1000000UL
#endif

#include<avr/io.h>
#include<util/delay.h>
void digital_value(int);
void ADC_initialization(void);
unsigned int ADC_read(unsigned int );

int main(void)
{
	unsigned int value;
	DDRC=0xff;
	ADC_initialization(); // Initialization of ADC
	while(1)
	{
		value=ADC_read(0);      // channel 0;
		digital_value(value);
	}
}

void ADC_initialization(void) // Initialization of ADC
{
	ADMUX=(1<<REFS0); // AVcc with external capacitor at AREF
	ADCSRA=(1<<ADEN)|(1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0);
	// Enable ADC and set Prescaler division factor as 128
}
unsigned int ADC_read(unsigned int x)
{
	ADMUX|=x; //selecting cannel
	ADCSRA|=(1<<ADSC); // start conversion
	while(!(ADCSRA & (1<<ADIF))); // waiting for ADIF, conversion complete
	ADCSRA|=(1<<ADIF); // clearing of ADIF, it is done by writing 1 to it
	return (ADC);
}

void digital_value(int value)
{
	if(value==0)
	{
		PORTC=0x00;
	}
	if ((value>0) &  (value < 100))
	{
		PORTC=0x01;
	}
	{
		if ((value >=100 )& (value < 200))
		PORTC =0x02;
	}
	if ((value >=200) & (value <300))
	{
		PORTC=0x03;
	}
	if ((value>=300) & (value < 400) )
	{
		PORTC =0x04;
	}
	if( (value >=400) & (value <500))
	{
		PORTC=0x05;
	}
	if (( value >=500) &( value <600) )
	{
		PORTC =0x06;
	}
	if ( (value >=600) & (value <700) )
	{
		PORTC =0x07;
	}
	if ( (value >=700) & (value <800) )
	{
		PORTC =0x08;
	}
	if ( (value >=800) & (value <900) )
	{
		PORTC =0x09;
	}
	if ( (value >=900) & (value <1024) )
	{
		PORTC =0x00;
		_delay_ms(250);
		PORTC=0X08;
		_delay_ms(250);
	}
}