MisterBotBreak
Published

How to Use Temperature and Humidity (DHT) Sensors

This project will show you how to use temperature and hmidity (DHT11 and DHT22) sensors with an Arduino card.

BeginnerProtip1 hour132,238
How to Use Temperature and Humidity (DHT) Sensors

Things used in this project

Hardware components

Arduino UNO
Arduino UNO
×1
Jumper wires (generic)
Jumper wires (generic)
×1
Resistor 10k ohm
Resistor 10k ohm
×1
DHT11 Temperature & Humidity Sensor (4 pins)
DHT11 Temperature & Humidity Sensor (4 pins)
Without driver
×1
DHT22 Temperature Sensor
DHT22 Temperature Sensor
Without driver
×1
Breadboard (generic)
Breadboard (generic)
×1

Software apps and online services

Arduino IDE
Arduino IDE

Story

Read more

Schematics

Connections DHT11 / 22

The connections for DHT11 are the same as those of the DHT22.

Code

Code for DHT22

Arduino
#include "DHT.h"
#define DHTPIN 2     
#define DHTTYPE DHT22   

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  Serial.println("DHTxx test!");

  dht.begin();
}

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

  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  float hif = dht.computeHeatIndex(f, h);
  float hic = dht.computeHeatIndex(t, h, false);

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

Code for DHT11

Arduino
#include "DHT.h"
#define DHTPIN 2     
#define DHTTYPE DHT11   

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  Serial.println("DHTxx test!");

  dht.begin();
}

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

  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  float hif = dht.computeHeatIndex(f, h);
  float hic = dht.computeHeatIndex(t, h, false);

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

Credits

MisterBotBreak

MisterBotBreak

48 projects • 150 followers
I love electronics and cats :D !

Comments

Related channels and tags
  • Arduino