volatile uint32_t count = 0;  // Holds the count of interrupts

const int  ledPinA= 4;
const int   ledPinB =5;
const int   ledPinC=6;
int stato=0;

void incrementCount() {
  count++;
}

void setup() {
  Serial.begin(115200);

  pinMode(2, INPUT_PULLUP);
  pinMode(ledPinA, OUTPUT);
  pinMode(ledPinB, OUTPUT);
  pinMode(ledPinC, OUTPUT);

  attachInterrupt(digitalPinToInterrupt(2), incrementCount, RISING);
}

void loop() {
  Serial.print("Interrupt count: ");
  noInterrupts();
  if(stato<2){
    stato++;
  }
  else{
   stato=0;
  }
  Serial.println(count);
  interrupts();
  
  switch(stato)
  {
    case 0:
    digitalWrite(ledPinA, HIGH);
    digitalWrite(ledPinB, LOW);
    digitalWrite(ledPinC, LOW);
    break;
    case 1:
    digitalWrite(ledPinB, HIGH);
    digitalWrite(ledPinA, LOW);
    digitalWrite(ledPinC, LOW);

    break;
    case 2:
    digitalWrite(ledPinC, HIGH);
    digitalWrite(ledPinB, LOW);
    digitalWrite(ledPinA, LOW);
    break;
    
 
  }
  delay(100);
}