// Include the DHT sensor library (Adafruit DHT library)
#include "DHT.h"

// Define the digital pin connected to the DATA pin of DHT22
#define DHTPIN 7     // Arduino UNO digital pin 10

// Define the type of DHT sensor
#define DHTTYPE DHT22 // Using DHT22 sensor

// Create a DHT object with specified pin and sensor type
DHT dht(DHTPIN, DHTTYPE);

void setup() {

  // Start serial communication at 9600 baud rate
  Serial.begin(9600);

  // Initialize the DHT sensor
  dht.begin();
}

void loop() {

  // Wait 2 seconds between readings
  // DHT22 requires minimum 2 seconds delay
  delay(2000);

  // Read temperature value in Celsius
  float temperature = dht.readTemperature();

  // Read humidity value in percentage
  float humidity = dht.readHumidity();

  // Check if sensor reading failed
  // isnan() checks for invalid (Not a Number) values
  if (isnan(temperature) || isnan(humidity)) {

    // Print error message if reading fails
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Print temperature value
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" °C\t");

  // Print humidity value
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");
}