interrupts_array.ino

const int buttonPin = 2;

const int NUM_READINGS = 9;
volatile int myReadings[] = {0,0,0,0,0,0,0,0,0};
const int TRIGGER_COUNT = 5;

void setup() {
  // put your setup code here, to run once:

  Serial.begin(38400);

  pinMode(buttonPin, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(2), getReadings, FALLING); 
}

void loop() {
  delay(1000);
  
  int count = 0;
  noInterrupts(); //cli();
  for (int i = 0; i < NUM_READINGS; i++){
    if (myReadings[i] > 0) count++;
  }
  interrupts(); //sei()
  
  if (count > TRIGGER_COUNT) Serial.println("Trigger is Go!");
  else Serial.println("Not enough to trigger.");
}

void getReadings(){
  for (int i = 0; i < NUM_READINGS; i++){
    myReadings[i] = digitalRead(i+4);
  }
}