Working ADC Code atmega8

adc.c

/*
 * ADC_TEST1.cpp
 *
 * Created: 2/20/2018 01:02:14 PM
 * Author : Arnob
 */ 
#define F_CPU 12000000UL
#include <avr/io.h>

int adc_value;       	//Variable used to store the value read from the ADC converter

void adc_init(void){
	ADCSRA |= ((1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0));    //16Mhz/128 = 125Khz the ADC reference clock
	ADMUX |= (1<<REFS0);                //Voltage reference from Avcc (5v)
	ADCSRA |= (1<<ADEN);                //Turn on ADC
	ADCSRA |= (1<<ADSC);                //Do an initial conversion because this one is the slowest and to ensure that everything is up and running
}



uint16_t read_adc(uint8_t channel){
	ADMUX &= 0xF0;                    //Clear the older channel that was read
	ADMUX |= channel;                //Defines the new ADC channel to be read
	ADCSRA |= (1<<ADSC);                //Starts a new conversion
	while(ADCSRA & (1<<ADSC));            //Wait until the conversion is done
	return ADCW;                    //Returns the ADC value of the chosen channel
}


int main(void){

	DDRB |= (1<<PB0);    	//PB5/digital 13 is an output

	adc_init();

	while(1){            //The infinite loop

		adc_value = read_adc(5);    //Read the ADC value, really that's just it
		if(adc_value > 500 && adc_value < 650) {
			PORTB = 0xff;    //If ADC value is above 512 turn led on
		}
		else if(adc_value > 700 && adc_value < 800) {
			PORTB = 0xff;    //If ADC value is above 512 turn led on
		}

		else {
			PORTB = 0x00;    //Else turn led off
		}
	}

	return 0;
}