06 Experiment

Intensity variation of LED based on potentiometer value

Source and description

http://sincgrid.in/avr-tutorials/avr-tutorial-experiment-6/

http://sincgrid.in/avr-tutorials/avr-tutorial-experiment-6/

#include <avr/io.h>
#define F_CPU 16000000UL
#include <avr/delay.h>

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

int main(void){

//    unsigned char i=0;

    DDRD|= _BV(DDD6);    //Set our pwm pin as an output

    //Timer configuration
    TCCR0A = ((1<<COM0A1)|(1<<WGM01)|(1<<WGM00));    //Enable pwm mode in pin PD6 and set the WGM bits to Fast pwm mode
    TCCR0B = ((1<<CS01)|(1<<CS00));                  //Set prescaler to 32

    ADCSRA |= ((1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0));    //Prescaler at 128 so we have an 125Khz clock source
    ADMUX |= (1<<REFS0);
    ADMUX &= ~(1<<REFS1);                        //Avcc(+5v) as voltage reference
    ADCSRB &= ~((1<<ADTS2)|(1<<ADTS1)|(1<<ADTS0));    //ADC in free-running mode
    ADCSRA |= (1<<ADATE);                        //Signal source, in this case is the free-running
    ADCSRA |= (1<<ADEN);                        //Power up the ADC
    ADCSRA |= (1<<ADSC);                        //Start converting

    for(;;)
    {

    adc_value = ADCW;    
    OCR0A = adc_value/4 - 24;
    _delay_ms(1000);

    }

    return 0;
}