Arduino Interface LDR.JPG


  Lets measure the light in the room with LDR
  Turns on an LED on , then off , repeatedly according to the Light.
// Pin 13 has an LED connected on most Arduino boards.
// LDR is connected to analog input A0 as shown in Diagram.
// give it a name:
int led = 13;
// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);     
// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);               // wait for a second