int input_pin = 2;
volatile int valume;

void setupTimer3(){
  noInterrupts();
    TCCR3A = 0;
    TCCR3B = 0;
    TCNT3 = 0;
  
  OCR3A = 15624;

  TCCR3B |= (1 << WGM32);
  TCCR3B |= (1 << CS32) | (1 << CS30);
  TIMSK3 |= (1 << OCIE3A);
  interrupts();
}

void setup(){
  pinMode(input_pin, INPUT);
  attachInterrupt(digitalPinToInterrupt(input_pin), state, RISING);
  DDRC = 0xFF;
  setupTimer3();
  Serial.begin(9600);
}

void loop(){

  PORTC = (1<<PC4) | (1<<PC5) | (1<<PC6) | (1<<PC7);
  delay(1000);
  PORTC = (0<<PC4) | (0<<PC5) | (0<<PC6) | (0<<PC7);
  delay(1000);

}

void state(){
  valume = digitalRead(input_pin);
  Serial.print("Input reading: ");
  Serial.println(valume);
}

ISR(TIMER3_COMPA_vect){
  PORTC ^= (1<<PC0) | (1<<PC1) | (1<<PC2) | (1<<PC3);
}