volatile unsigned long countRise = 0;
volatile unsigned long us, prevPulseUs, pulseUs, countRiseCopy;

void setup() {
  Serial.begin(115200);
  pinMode(2, INPUT);
  attachInterrupt(digitalPinToInterrupt(2), pin_ISR, RISING);
}

void loop() {
    noInterrupts();
    countRiseCopy = countRise;
    interrupts();
  
  Serial.println(countRiseCopy);
  delay(1000);
}

void pin_ISR() {
  us = micros();
  if ((us - pulseUs) > 750) {  // debounce
    prevPulseUs = pulseUs;
    pulseUs = us;
    countRise++;
  }
}