/********************************
  name: 5V relay module and DHT 11/22/21 humidity and temperature sensor module
  function: This program shows how the temperature and humidity sensor turns on
            devices or power sockets connected to 5V relay module
  email: info.acoptex@gmail.com
  web: http://acoptex.com
********************************/
#include <DHT.h> // include libraries
#include <Wire.h>
#include <LCD.h>
#include <LiquidCrystal_I2C.h>

const int relayPin = 8;
const int DHTPIN = A0;

// Uncomment whatever type you're using!
#define DHTTYPE DHT11   // DHT 11
//#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321
//#define DHTTYPE DHT21   // DHT 21 (AM2301)

DHT dht(DHTPIN, DHTTYPE);// Initialize DHT sensor
LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);//Initialise the LCD 1602 I2C module
/********************************/
void setup() {
  Serial.begin(9600);
  pinMode(relayPin, OUTPUT);
  dht.begin();
}

void loop()
{
  //Define the LCD as 16 column by 2 rows
  lcd.begin (16, 2);
  //Switch on the backlight
  lcd.setBacklight(HIGH);
  
  // Reading temperature or humidity takes about 250 milliseconds!
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  float h = dht.readHumidity();
  // Read temperature as Celsius (the default)
  float t = dht.readTemperature();
  // Read temperature as Fahrenheit (isFahrenheit = true)
  float f = dht.readTemperature(true);

  // Check if any reads failed and exit early (to try again).
  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }
  //goto first column (column 0) and first line (Line 0)
  lcd.setCursor(0, 0);
  lcd.print("Temp = ");
  lcd.print(t);
  lcd.print(" *C ");
  lcd.setCursor(0, 1);
  lcd.print(" Hum = ");
  lcd.print(h);
  lcd.print(" % ");
 
  Serial.print("Temperature = ");
  Serial.print(t);
  Serial.print(" *C ");
  Serial.print("Temperature = ");
  Serial.print(f);
  Serial.print(" *F ");
  Serial.print("Humidity = ");
  Serial.print(h);
  Serial.print(" %\t ");
  Serial.println();
  if (h >= 66) { // you can change humidity value here - h>=66 to your preffered number
    digitalWrite(relayPin, LOW);
  }
  else {
    digitalWrite(relayPin, HIGH);
  }
if (t >= 26) {// you can change temperature value here - t>= 30 to your preferred number or change from Celsius to Fahrenheit readings
 digitalWrite(relayPin, LOW);
 }
 else {
 digitalWrite(relayPin, HIGH);
  }
  delay(1000);// 1 second delay between measurements
}