unsigned long timeOld = 0;
unsigned long timeNew = 0;

const int start = 23;
const int stop = 22;

void setup() {
  // put your setup code here, to run once:
  pinMode(start, INPUT);
  pinMode(stop, INPUT);
  Serial.begin(115200);
  Serial.println("Setup done");
}

void loop() {
  // put your main code here, to run repeatedly:
if()  
}