How PIR Sensor Works and How To Interface It with Arduino

1#include <LiquidCrystal.h> // Include the LiquidCrystal library for LCD display
2LiquidCrystal lcd(12, 11, 6, 7, 8, 9); // Initialize the LCD object with pin numbers
3
4int sensorInput = 2;   // PIR sensor input pin
5int sensorReturn = 0;  // Variable to store PIR sensor output
6
7void setup() {
8  pinMode(sensorInput, INPUT); // Set sensor pin as input
9  // Set up the LCD's number of columns and rows
10  lcd.begin(16, 2);
11  // Print initial message on the LCD
12  lcd.setCursor(0, 0);
13  lcd.print("PIR Sensor Says:");
14  lcd.setCursor(0, 1);
15}
16
17void loop() {
18  sensorReturn = digitalRead(sensorInput); // Read input value from PIR sensor
19  
20  // Check if motion is detected
21  if (sensorReturn == HIGH) {
22    // Set cursor to the second row and print motion detection message
23    lcd.setCursor(0, 1);
24    lcd.print("Motion Occurs   ");
25  } else {
26    // Set cursor to the second row and print motion stopped message
27    lcd.setCursor(0, 1);
28    lcd.print("Motion Stops    ");
29  }
30}