/ESP8266-DHT22-DisplayFlutter

Primary LanguageC++

ESP8266 DHT22 Temperature and Humidity Monitor with SSD1306 OLED Display

This project demonstrates how to read temperature and humidity data from a DHT22 sensor using an ESP8266 microcontroller and display the results on an SSD1306 OLED display.

Components Required

  • ESP8266 NodeMCU or any compatible ESP8266 module
  • DHT22 Temperature and Humidity Sensor
  • SSD1306 OLED Display (128x64)
  • Jumper wires
  • Breadboard (optional)

Pin Connections

DHT22 Connections

DHT22 Pin ESP8266 Pin Description
VCC 3.3V Power supply
GND GND Ground
DATA D5 (GPIO 14) Digital signal

SSD1306 Connections

SSD1306 Pin ESP8266 Pin Description
VCC 3.3V Power supply
GND GND Ground
SDA D2 (GPIO 4) Data line
SCL D1 (GPIO 5) Clock line

Note: Ensure that the ESP8266 is powered with 3.3V, as higher voltages can damage the board.

Libraries Required

You will need to install the following libraries through the Arduino Library Manager:

  1. Adafruit SSD1306: For controlling the OLED display.
  2. Adafruit GFX: Required for graphical functions.
  3. DHT sensor library: For reading data from the DHT22 sensor.
  4. ESPAsyncWebServer: For creating a web server to serve sensor data.

To install these libraries, follow these steps:

  1. Open the Arduino IDE.
  2. Go to Sketch > Include Library > Manage Libraries...
  3. Search for and install:
    • Adafruit SSD1306
    • Adafruit GFX
    • DHT sensor library
    • ESPAsyncWebServer
    • ESPAsyncTCP (may be required for ESPAsyncWebServer)

Code Upload

  1. Open the Arduino IDE.
  2. Copy the provided code into a new sketch.
  3. Replace the following lines in the code with your Wi-Fi network credentials: 
    const char* ssid = "YOUR_SSID"; // Replace with your Wi-Fi network name
const char* password = "YOUR_PASSWORD"; // Replace with your Wi-Fi password
  4. Select your ESP8266 board from Tools > Board > NodeMCU 1.0 (ESP-12E Module) (or whichever ESP8266 board you are using).
  5. Connect your ESP8266 to your computer via USB.
  6. Select the correct COM port from Tools > Port.
  7. Click the upload button to compile and upload the code to your ESP8266.

Accessing the Data

After uploading the code and connecting the ESP8266 to your Wi-Fi, you can read the temperature and humidity data in two ways:

  1. Through Serial Connection:

    • Open the Serial Monitor in the Arduino IDE (set to 115200 baud rate).
    • You will see the temperature and humidity values printed in the Serial Monitor output.

  2. Via Web Browser:

    • Open the Serial Monitor to find the IP address assigned to the ESP8266 by your router.
    • Enter the IP address in a web browser to access the temperature and humidity readings. The readings will be updated every 10 seconds.

Display

The OLED display will show the current temperature and humidity values read from the DHT22 sensor.

Troubleshooting

  • Ensure all connections are secure and correct.
  • Check the Serial Monitor for error messages or connection issues.
  • If the display does not initialize, check the I2C connections and ensure the correct address is set in the code.

License

This project is open-source and available for modification and redistribution. Enjoy building and experimenting!