How to operate LDR using Arduino uno (with analog input)

How to operate LDR using Arduino uno (with analog input)

/*
*How to operate LDR using Arduino uno (with analog input)
*This code discribes that how an Light dependent resistor can be operated with analog input using Arduino Uno.
*
*Copyright (C) 2007 Free Software Foundation, Inc. <[email protected]>
*
*for more detail please visit:https://www.arduinounomagic.com/2019/01/how-to-operate-ldr-using-arduino-uno.html
*
*for more projects based on Arduino uno please visit: https://arduinounomagic.com/
*/



#define LDR A2 //Light dependent resisotr (LDR) connected to analog pin A2 
#define LED 5 //LED connected to digital pin 5
int LDR_value; //variable to store result value read by LDR

void setup()
{
Serial.begin(9600); //intialize the serial port for communicaion
pinMode(LED, OUTPUT); // set LED as output
pinMode(LDR, INPUT); //set light dependent resistor as input

}

void loop()
{

 LDR_value=analogRead(LDR); //read the data from analog pin A2 and store in LDR_value

if (LDR_value<=300) //if LDR_value value is less than or equal to 300 that means its dark outside so LED should be turn on

{
   digitalWrite(LED, HIGH);//turn on the LED
   
  
  Serial.println("its dark turn on the LED");// display "its dark turn on the LED" on serial monitor and set the cursor to the new line
  Serial.println("LDR value:"); //display "LDR value:" on serial monitor and set the cursor to the new line
  Serial.println(LDR_value); // print the value of sensor
 
}
else //if LDR_value value is greater than 300 that means its bright outside so LED should be turn off
{
    digitalWrite(LED, LOW); //turn off the LED
  
 
    Serial.println("its bright turn off the LED"); // display "its bright turn off the LED" on serial monitor and set the cursor to the new line
    Serial.println("LDR value:"); //display "LDR value:" on serial monitor and set the cursor to the new line
    Serial.println(LDR_value); // print the value of sensor
}
delay(200); //delay

}