AVRFreaks.net

#include <avr/io.h>
#include <avr/interrupt.h>

void initSpeaker()
{
   // Set PORTC0-1's data direction as output
   DDRC |= (1 << 0) | (1 << 1);
}
void initTimer0 ()
{
   // Setup timer 0, CTC mode, no pre-scaler
   TCCR0A |= (1 << CS10) | (1 << WGM12);
   // Enable CTC interrupt
   TIMSK0 |= (1 << OCIE0A);
   
}
void initTimer1 ()
{
   // Setup timer 1, CTC mode, no pre-scaler
   TCCR1A |= (1 << CS10) | (1 << WGM12);
   // Enable CTC interrupt
   TIMSK1 |= (1 << OCIE1A);
   
}
void changePitchT0 ()
{
   // Set timer 0 CTC compare number
   OCR0A = 18181;
}
void changePitchT1 ()
{
   // Set timer 1 CTC compare number
   OCR1A = 13620;
}
int main(void)
{
   initSpeaker();
   initTimer0();
   changePitchT0();
   initTimer1();
   changePitchT1();
   sei(); // Enable interrupts
   
    while(1)
    {
        // tbc
   }      
}

// Timer 0 compare routine
ISR(TIMER0_COMPA_vect)
{
   // Toggle the output
   PORTC ^= (1 << 0);
   
}

// Timer 1 compare routine
ISR(TIMER1_COMPA_vect)
{
   // Toggle the output
   PORTC ^= (1 << 1);
}

void initSpeaker()
{
   // Set PORTB1-2's data direction as output
   DDRB |= (1 << 1) | (1 << 2);
}
void initTimer1 ()
{
   // Setup timer 1, CTC mode, no pre-scaler, OUTPUT COMPARE ON BOTH PINS?
   TCCR1A |= (1 << WGM10) | (1 <<COM1A0) | (1 << COM1B0);
   // Enable interrupt flag?
   TIFR1 |= (1 << OCF1A);
   // Enable CTC interrupt
   TIMSK1 |= (1 << OCIE1A);
   
}
void initTimer2 ()
{
   // Setup timer 2, CTC mode, no pre-scaler
   TCCR2A |= (1 << CS10) | (1 << WGM12);
   // Enable interrupt flag?
   TIFR2 |= (1 << OCF2A);
   // Enable CTC interrupt
   TIMSK2 |= (1 << OCIE2A);
   
}
void changePitchT1 ()
{
   // Set timer 0 CTC compare number
   OCR1A = 18181;
}
void changePitchT2 ()
{
   // Set timer 1 CTC compare number
   OCR2A = 13620;
}
void setPulseWidth()
{
   // tbc   
}
void setOctave()
{
   // tbc   
}
void setTranspose()
{
   // tbc   
}
void setChord()
{
   // tbc   
}

int main(void)
{
   initSpeaker();
   initTimer1();
    changePitchT1();
    initTimer2();
    changePitchT2();
   sei(); // Enable interrupts
   
    while(1)
    {
        // tbc
   }      
}

// Timer 1 compare routine
ISR(TIMER1_COMPA_vect)
{
   // Toggle the output
   PORTB ^= (1 << 1);
   
}

// Timer 2 compare routine
ISR(TIMER2_COMPA_vect)
{
   // Toggle the output
   PORTB ^= (1 << 2);
}

   TCCR2A |= (1 << CS10) | (1 << WGM12);

OCR2A = 13620;