Read Temperature & Humidity (DHT22 + Arduino)

// Read temperature + humidity from a DHT22 and print to Serial.
// Install "DHT sensor library" by Adafruit (Library Manager) first.

#include <DHT.h>

#define DHTPIN  2
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  dht.begin();
}

void loop() {
  delay(2000);                        // DHT22 refreshes every ~2 seconds
  float h = dht.readHumidity();
  float t = dht.readTemperature();    // Celsius (use readTemperature(true) for F)

  if (isnan(h) || isnan(t)) {
    Serial.println("Sensor read failed");
    return;
  }
  Serial.print("Temp: ");     Serial.print(t); Serial.print(" C   ");
  Serial.print("Humidity: "); Serial.print(h); Serial.println(" %");
}