int A, B, i=0;

void setup() {
  // put your setup code here, to run once:
  pinMode(2, INPUT);
  pinMode(3, INPUT);
  Serial.begin(38200);
  A = digitalWrite(2);
  B = digitalWrite(3);
  //attachInterrupt(digitalPinToInterrupt(2), blink, CHANGE);
  //attachInterrupt(digitalPinToInterrupt(3), blink, CHANGE);
}

void loop() {
  // put your main code here, to run repeatedly:



  if(A==B){
    if(A!=digitalRead(2)){
      i++;
      A = digitalRead(2);
    }
    if(B!=digitalRead(3)){
      i--;
      B = digitalRead(3);
    }
  }

  if(A!=B){
    if(A!=digitalRead(2)){
      i--;
      A = digitalRead(2);
    }
    if(B!=digitalRead(3)){
      i++;
      B = digitalRead(3);
    }
  }


  Serial.print("\n\n\n\n\n\n\n\n\n\n pulsos:");
  Serial.println(i);

}