LDR based night light project that automatically turns on the LED when the environment gets dark. Teaches automatic control logic with analog threshold comparison.

Video

Circuit Diagram

Source Code

1int value;
2
3void setup() {
4  pinMode(13, OUTPUT); 
5}
6
7void loop() {  
8  value = analogRead(A0);
9  
10  if (value < 50) {
11    digitalWrite(13, HIGH);
12  } else {
13    digitalWrite(13, LOW);
14  }
15}

Night Light with Ldr | BlueGrays