Arduino Door Lock with Smartphone Flashlight Login (Li-Fi project)

1#define Solenoid 12
2#define ldr 8
3int Buzzer = 4;
4int GreenLed = 6;
5int RedLed = 11;
6int val;
7int val2;
8String duration;
9
10void setup() {
11  // put your setup code here, to run once:
12  Serial.begin(9600);
13  pinMode(ldr, INPUT_PULLUP);
14  pinMode(Solenoid, OUTPUT);
15  pinMode(GreenLed, OUTPUT);
16  pinMode(RedLed, OUTPUT);
17  digitalWrite(RedLed, HIGH);
18}
19
20  void OpenDoor(){             //Lock opening function open for 3s
21 
22  digitalWrite(Solenoid,HIGH);
23  tone(Buzzer, 500);
24  digitalWrite(RedLed, LOW);
25  digitalWrite(GreenLed, HIGH);
26  
27  delay(3000);
28  digitalWrite(Solenoid,LOW);
29  noTone(Buzzer);
30  digitalWrite(RedLed, HIGH);
31  digitalWrite(GreenLed, LOW);
32}
33
34void loop() {
35  // put your main code here, to run repeatedly:
36  int val = digitalRead(ldr);
37  while(val == 0)
38  {
39    int val2 = digitalRead(ldr);
40    duration += val2;
41 
42    if(duration == "0001")
43    {
44
45      OpenDoor();
46    }
47  
48    if(val2 == 1)
49    {
50      duration = "";
51      break;
52    }
53
54
55    delay(200);
56  }
57
58}