Teste Interrupt

  #define  botao  2
  #define  LED  13
  byte cnt = 0;
  byte cnt2 = 0;
  char LED_status;
//-------------------------
  void setup()
  {
     pinMode(botao, INPUT);
     pinMode(LED, OUTPUT);
     attachInterrupt(0, PressDn, FALLING);
  }
//--------------------------
  void PressDn()
  {
     detachInterrupt(0);
//     noInterrupts();
     cnt2++;
     cnt = 0;
     LED_status = !LED_status;
     digitalWrite(LED, LED_status);
   }
//-------------------------
  void loop()
  {
    while(cnt == 0)
   {
//     interrupts();                            // 2a opção
       attachInterrupt(0, PressDn, FALLING);
     cnt = 1;
     while(cnt2 >= 3)
    {
      ;
    }
    }
  }