#include <LiquidCrystal_I2C.h>

#define PIR_SENSOR 10

LiquidCrystal_I2C lcd(0x27, 20, 4);
int pirState = LOW;

bool mot_flag = true;
bool nomot_flag = true;

void lcd_clear() {
    lcd.setCursor(0, 0);
    lcd.print("                ");
    lcd.setCursor(0, 1);
    lcd.print("                ");
}

void setup() {
  
   Serial.begin(9600);

  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);

  pinMode(PIR_SENSOR, INPUT);

}

void loop() {
  
  int current_pir = digitalRead(PIR_SENSOR);
  if (current_pir == HIGH) 
  {
    mot_flag = true;
    if(nomot_flag == true)
    {
      lcd_clear();
      nomot_flag = false;
    }
    lcd.setCursor(0, 0);
    lcd.print("Motion detected!");
  }
  else
  {
      nomot_flag = true;
      if(mot_flag == true)
      {
        lcd_clear();
        mot_flag = false;
      }
      lcd.setCursor(0, 0);
      lcd.print("No motion");
  }
  
}