Are you fascinated by the world of electronics and eager to start a hands-on project? This guide will help you create a sleek, functional temperature monitor using an Arduino Nano, a DHT22 sensor, and a vibrant OLED display. Whether you're a seasoned tinkerer or a curious beginner, this project is perfect for diving into the exciting realm of Arduino. By the end of this guide, you'll have a working device that accurately displays temperature and humidity, making it a practical addition to your home or a stepping stone for more complex projects.

 

Parts List:

• Arduino Nano (or most other Arduinos)
• USB cable for Arduino
• 0.96" OLED Display SSD1306
• DHT22 temperature and humidity sensor
• Jumper wires

 

Software Requirements:

• Arduino IDE (Either online or installed works)
• "Adafruit SSD1306" library by Adafruit
• "DHT sensor library" by Adafruit

 

Step 1: Install Libraries

1. Open the Arduino IDE.
2. Go to Sketch > Include Library > Manage Libraries.
3. In the Library Manager, search for "Adafruit SSD1306".
4. Click on the result and click Install All.
5. Search for "DHT sensor library" by Adafruit.
6. Click on the result and click Install All.

 

Step 2: Wiring

Refer to the wiring diagram below and use the following wiring key to connect your components.

 

Wiring Key:

DHT22 Sensor

• VCC to 5V
• GND to GND
• DATA to D2 (or any digital pin)

SSD1306 OLED Display

• VCC to 3.3V
• GND to GND
• SCL to A5 (or SCL)
• SDA to A4 (or SDA)

 

Wiring Diagram:

 

Step 3: Code

Upload the following code to your Arduino to start monitoring the temperature and humidity:

/*
 * Temprature & Humidity Arduino Project using DHT22 Sensor and 0.96 OLED Display
 * 
 * https://zaitronics.com.au/blogs/main/building-an-arduino-temperature-monitor-with-dht22-and-0-96-oled-display
 * 
 * by Ethan - Zaitronics
 */
 
#include <Arduino.h>
#include <U8g2lib.h>
#include "DHT.h"

#define DHTPIN 2     // which pin we're connected to
#define DHTTYPE DHT22   // DHT 22  (AM2302)
DHT dht(DHTPIN, DHTTYPE);

#ifdef U8X8_HAVE_HW_SPI
#include <SPI.h>
#endif
#ifdef U8X8_HAVE_HW_I2C
#include <Wire.h>
#endif


  U8G2_SSD1306_128X64_NONAME_1_HW_I2C u8g2(U8G2_R0, /* reset=*/ U8X8_PIN_NONE);

void draw(void) {
  //  // graphic commands to redraw the complete screen should be placed here
  float h = dht.readHumidity();
  // Read temperature as Celsius
  float t = dht.readTemperature();
  // Read temperature as Fahrenheit
  float f = dht.readTemperature(true);

  u8g2.setFont(u8g2_font_helvB10_tf);
  u8g2.setCursor(0, 16);
  u8g2.print("Temp & Humidity");
  u8g2.setFont(u8g2_font_helvB18_tf);
  u8g2.setCursor(0, 42);
  u8g2.print("T= "); u8g2.print(t); u8g2.print(" °C");
  u8g2.setCursor(0, 64);
  u8g2.print("H= "); u8g2.print(h); u8g2.print(" %");
}

void setup(void) {
  
  dht.begin();

  u8g2.begin();  
}

void loop(void) {

    // Wait a few seconds between measurements.
  delay(2000);

  // 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();
  // Read temperature as Celsius
  float t = dht.readTemperature();
  
  u8g2.firstPage();
  do {
    draw();
  } while ( u8g2.nextPage() );
  delay(1000);
}

 

Results:

Once you have completed the wiring and uploaded the code, your Arduino temperature monitor will start displaying the temperature and humidity readings on the OLED display. This project is a great way to get started with Arduino and sensor integration.

 

Note: Ensure that the DHT22 sensor and OLED display are connected properly to avoid issues with the readings and display output. If you encounter any problems, double-check the wiring and comment below if you need any more help