#include <LiquidCrystal_I2C.h>

const LiquidCrystal_I2C LCD(0x27, 16, 2);

const byte sensorPin = 3;

void inputFromSensor() {
  LCD.init();
  LCD.print("Motion Detected!");
  delay(100);

  LCD.init();
  LCD.print("No Motion");
}

void setup() {
  // put your setup code here, to run once:
  pinMode(sensorPin, INPUT_PULLUP);

  LCD.init();
  LCD.backlight();
  LCD.setCursor(0, 0);
  LCD.print("No Motion");
}

void loop() {
  // put your main code here, to run repeatedly:
  if (digitalRead(sensorPin) == HIGH) {
    inputFromSensor();
  }
}