Building a Temperature and Humidity Monitor with DHT11 and Arduino

Introduction

This tutorial will walk you through the steps to build a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino. This project is ideal for beginners in electronics and programming. You'll learn how to wire the DHT11 sensor to the Arduino, write the code, and display the data on a serial monitor.

Step 1: Gather Your Materials

Before starting, make sure you have the following components:

• DHT11 Sensor
• Arduino Uno
• Jumper wires
• Breadboard

Step 2: Connect the DHT11 to Arduino

To connect the DHT11 sensor to the Arduino, follow the wiring diagram below:

Step 3: Write the Arduino Code

Now, let's write the code for the Arduino to read data from the DHT11 sensor. The following code will initialize the sensor and read the temperature and humidity values.

#include 

#define DHTPIN 2          // Pin connected to DHT11
#define DHTTYPE DHT11     // DHT 11
DHT dht(DHTPIN, DHTTYPE);

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

void loop() {
  delay(2000);  // Wait for 2 seconds between readings

  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

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

  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.print("%  Temperature: ");
  Serial.print(temperature);
  Serial.println("°C");
}
            

Step 4: Upload and Test

Upload the code to your Arduino board and open the Serial Monitor to view the real-time temperature and humidity data. If everything is set up correctly, you should see the readings displayed in the Serial Monitor.

Step 5: Troubleshooting

If you're encountering issues, ensure the following:

• The DHT11 is correctly connected to the specified pin.
• The DHT library is installed in the Arduino IDE.
• Check the Serial Monitor baud rate (it should be 9600).