#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27, 16, 2);
int ledPin = 13;    
int inputPin = 9;               
int pirState = LOW;             
int val = 0;
#define SPEAKER_PIN 8
void setup() {
  pinMode(ledPin, OUTPUT);   
  pinMode(SPEAKER_PIN, OUTPUT);   
  pinMode(inputPin, INPUT);     
  Serial.begin(9600);
  lcd.init();
  lcd.backlight();
  lcd.clear();
}

void loop() {
  val = digitalRead(inputPin);  
  if (val == HIGH) {            
    digitalWrite(ledPin, HIGH);  
    if (pirState == LOW) {
      Serial.println("Motion detected!");
      pirState = HIGH;
      lcd.setCursor(3, 0);
      lcd.print("WARNING!!!");
    }
  } else {
    digitalWrite(ledPin, LOW); 
    if (pirState == HIGH) {
      // we have just turned of
      Serial.println("Motion ended!");
      pirState = LOW;
      lcd.clear();
    }
  }
}