millis1

int lightPin = A5;
int ledPin = 6;
unsigned long time1;
unsigned long s_time;

void setup (){
  pinMode(ledPin,OUTPUT);
  Serial.begin(9600);
  s_time = millis();
  Serial.print("s_time=");
  Serial.println(s_time);
}

void loop(){
  //Serial.println (analogRead(lightPin));
  if (analogRead(lightPin)>700){
    Serial.println(millis()-s_time);
    delay(100000);

  }
}