#include <Servo.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include <LiquidCrystal_I2C.h>      // подключаем библиотеку дисплея

const int SERVO_PIN  = 5; // Arduino pin connected to Servo Motor's pin
const int SENSOR_PIN = 2; // Arduino pin connected to DS18B20 sensor's DATA pin
const float TEMPERATURE_THRESHOLD = 20;  // °C
const float TOLERANCE             = 0.5; 
LiquidCrystal_I2C lcd(0x27, 16, 2);// °C

Servo servo; // create servo object to control a servo
OneWire oneWire(SENSOR_PIN);         // setup a oneWire instance
DallasTemperature sensor(&oneWire); // pass oneWire to DallasTemperature library
float temperature;
int angle;

void setup() {
  Serial.begin(9600);      // initialize serial
  servo.attach(SERVO_PIN); // attaches the servo on pin 9 to the servo object
  servo.write(0);
  sensor.begin();     // initialize the sensor
  lcd.init();           // инициализация
  lcd.backlight();      // включить подсветку     
}

void loop() {
  sensor.requestTemperatures();             // send the command to get temperatures
  temperature = sensor.getTempCByIndex(0);  // read temperature in Celsius


  if (temperature > (TEMPERATURE_THRESHOLD + TOLERANCE))
    angle = 90; // set angle to 90 degree
  else if (temperature < (TEMPERATURE_THRESHOLD - TOLERANCE))
    angle = 0;  // set angle to 0 degree

  servo.write(angle);  // rotate servo motor
  lcd.home();             // курсор в 0,0
  lcd.print(temperature);  // выводим температуру
  lcd.write(223);         // символ градуса
  lcd.print("C  ");       // С и пара пробелов для очистки
  // print to serial
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print("°C => servo angle: ");
  Serial.println(angle);
}