Temperature Monitoring with DHT22

DHT22 Temperature & Humidity Monitor

The DHT22 sensor is a reliable digital sensor used to measure temperature and humidity with good accuracy and stability. In this tutorial, you will learn how to read temperature and humidity data from the DHT22 sensor using an Arduino Uno and display the values via the Serial Monitor. This project is suitable for environmental monitoring, automation, and academic prototypes.

Required Components

• Arduino Uno

• DHT22 Temperature & Humidity Sensor

• 10kΩ Resistor (pull-up resistor)

• LCD Display (optional)

• Jumper Wires

• Breadboard

How It Works

The DHT22 communicates with the Arduino using a single digital data pin. When the Arduino sends a request signal, the sensor responds with calibrated digital data representing temperature and humidity values. The Arduino then processes these values and displays them on the Serial Monitor or other output devices.

Library Installation

To use the DHT22 sensor, install the required library:

1. Open the Arduino IDE

2. Go to Sketch > Include Library > Manage Libraries

3. Search for "DHT sensor library" by Adafruit

4. Click Install

Circuit Connection

• Connect VCC of the DHT22 to 5V on the Arduino

• Connect GND to GND

• Connect the DATA pin to Digital Pin 2 on the Arduino

• Place a 10kΩ pull-up resistor between VCC and DATA pin

Code Example

#include <DHT.h>

#define DHTPIN 2        // Pin connected to DHT22 data pin
#define DHTTYPE DHT22   // Define sensor type

DHT dht(DHTPIN, DHTTYPE);

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

void loop() {
  float temperature = dht.readTemperature(); // Read temperature in Celsius

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

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");

  delay(2000);
}