pir.ino

int const PIRpin = 2;
unsigned long previousMillis = 0;
const long interval = 2000;

int prevPinStatus = 0;
long presenceCounter = 0;

void setup() {
  Serial.begin(9600);
  pinMode(PIRpin, INPUT);
  prevPinStatus = digitalRead(PIRpin);
}

void loop() {
  int PIRstatus = digitalRead(PIRpin);

  if (PIRstatus == 1) {
    presenceCounter++;
    if (presenceCounter > 10) {
      unsigned long currentMillis = millis();
      if (currentMillis - previousMillis >= interval) {
        previousMillis = currentMillis;
        Serial.println("In");
        presenceCounter = 0;
      }
    }
  } else {
    presenceCounter = 0;
  }
}