//SDA = A4, SCL = A5;
const unsigned long TSec=1000;
unsigned long Num_ms, Num_sec,Num_min; 
unsigned long Num_heur,Temps_ms;
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
#include <DHT.h>
#define DHTPIN 2      // Pin where the sensor is connected
#define DHTTYPE DHT22 // Sensor type "normally is DHT11"
const int trig = 4;
const int echo = 5;
const int led = 0;
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  pinMode(trig, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(led, OUTPUT);
  lcd.init();
  lcd.backlight();
  delay(10);
  Serial.begin(9600);
  dht.begin();
}

void loop() {
  long duration, distance;
digitalWrite(trig, LOW);
delayMicroseconds(2);
digitalWrite(trig, HIGH);
delayMicroseconds(10);
digitalWrite(trig, LOW);
duration = pulseIn(echo, HIGH);
distance = (duration/2) / 29.1;

if (distance < 20) {
Serial.print(distance);
Serial.println(" cm");
digitalWrite(led, HIGH);
} else if (distance>20) {
Serial.print(distance);
Serial.println(" cm");
digitalWrite(led, LOW);
 }
  float humidity = dht.readHumidity();
  float temperatureC = dht.readTemperature();

  if (isnan(humidity) || isnan(temperatureC)) {
    Serial.println("Error reading data!");
    return;
  } else {

  // Output data to the serial monitor
  Serial.print("Temperature: ");
  Serial.print(temperatureC);
  Serial.print("°C, ");

  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println("%");
  lcd.setCursor(0,1);
   lcd.print("t=");
   lcd.print(temperatureC);
   lcd.print("C.");
   lcd.print("h=");
   lcd.print(humidity);
   lcd.print("%");

  }
Temps_ms=millis(); 
  Num_sec= (Temps_ms/TSec)%60;
  Num_min= (Temps_ms/(TSec*60))%60;
  Num_heur= (Temps_ms/(TSec*3600))%60;
  Serial.print(Num_heur);Serial.print(":");
  Serial.print(Num_min);Serial.print(":");
  Serial.println(Num_sec);
  lcd.setCursor(0, 0);
  lcd.print(Num_heur);lcd.print(":");lcd.print(Num_min);lcd.print(":");lcd.print(Num_sec);
  delay(1000); 
}