void setup() {
  pinMode(2, INPUT);
  digitalWrite(2,HIGH);

  attachInterrupt(digitalPinToInterrupt(2),ano,FALLING);
  Serial.begin(9600);
}

void loop() {
  delay(1000);

}

void ano(){
  int pot = analogRead(A0);

  int mapa = map(pot,0,1023,0,100);
  Serial.println(String(mapa) + "%");
}