Arduino Code for 2nd EE Summer Camp © 2015 by K-ways.

DHT.ino

#include "DHT.h"
#define DHTPIN 3
#define DHTTYPE DHT11

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  Serial.println("Initializing...");
  pinMode(2, OUTPUT);
  pinMode(5, OUTPUT);
  digitalWrite(2, HIGH);
  digitalWrite(5, LOW);
  dht.begin();
}

void loop() {
  delay(2000);
  
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  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;
  }

  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.print(" *C ");
  Serial.print(f);
  Serial.println(" *F\t");
}

DHT_LED.ino

#include "DHT.h"
#define DHTPIN 3
#define DHTTYPE DHT11

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  Serial.println("Initializing...");
  pinMode(2, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(13, OUTPUT);
  digitalWrite(2, HIGH);
  digitalWrite(5, LOW);
  digitalWrite(13, LOW);
  dht.begin();
}

void loop() {
  delay(2000);
  
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  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;
  }

  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.print(" *C ");
  Serial.print(f);
  Serial.println(" *F\t");
  
  if ( t >= 30 || h >= 75 ){
    digitalWrite(13, HIGH);
  }
  else{
    digitalWrite(13, LOW);
  }
}