DTH-11

// Example testing sketch for various DHT humidity/temperature sensors

// Written by ladyada, public domain

#include "DHT.h"

#define DHTPIN 2     // what pin we're connected to

// Uncomment whatever type you're using!

#define DHTTYPE DHT11   // DHT 11 

//#define DHTTYPE DHT22   // DHT 22  (AM2302)

//#define DHTTYPE DHT21   // DHT 21 (AM2301)

// Connect pin 1 (on the left) of the sensor to +5V

// Connect pin 2 of the sensor to whatever your DHTPIN is

// Connect pin 4 (on the right) of the sensor to GROUND

// Connect a 10K resistor from pin 2 (data) to pin 1 (power) of the sensor

DHT dht(DHTPIN, DHTTYPE);

void setup() {

  Serial.begin(9600); 

  Serial.println("DHT11 test!");

  dht.begin();

}

void loop() {

  // 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();

  float t = dht.readTemperature();

  // check if returns are valid, if they are NaN (not a number) then something went wrong!

  if (isnan(t) || isnan(h)) {

    Serial.println("Failed to read from DHT");

  } else {

    Serial.print("Humidity: "); 

    Serial.print(h);

    Serial.print(" %\t");

    Serial.print("Temperature: "); 

    Serial.print(t);

    Serial.println(" *C");

  }

}