#include <LiquidCrystal_I2C.h>
#define LED_pin 2
#define PMS_digitalin 12
#define NTC_analogin 14

LiquidCrystal_I2C LCD = LiquidCrystal_I2C(0x27, 22, 21);

void setup() {
  pinMode(LED_pin, OUTPUT);
  pinMode(PMS_digitalin, INPUT);
  pinMode(NTC_analogin, INPUT);
  LCD.init();
  Serial.begin(9600);
}

void loop() {
  
  // When a motion is detected, keep reading the temperature from the temperature 
// sensor and print the temperature on the LCD display
  int PMS_in = digitalRead(PMS_digitalin);
  if (PMS_in == 1) {
    int LED_status = digitalRead(LED_pin);
    int NTC_in = analogRead(NTC_analogin);
    float celsius = 1 / (log(1 / (4095. / NTC_in - 1)) / 3950 + 1.0 / 298.15) - 273.15;
    LCD.setCursor(0, 0);
    LCD.print("Temperature:");
    LCD.setCursor(0, 1);
    LCD.println(celsius);

    // If the temperature is below 10 ℃ when a motion is detected, turn on LED and 
// print the “LED On” on the LCD display.
    if (celsius < 10) {
      digitalWrite(LED_pin, HIGH);
      LCD.setCursor(0, 2);
      LCD.println("LED On");
    }
  }
  
  //  When the OUT pin of the motion sensor goes LOW, turn off LED and clean the 
// LCD display. 
  else {
    digitalWrite(LED_pin, LOW);
    LCD.clear();
  }

  delay(1000);
}