How to Configure ESP32 Wi-Fi with AsyncWebServer for Dynamic HTML Pages

Introduction

In this tutorial, we will guide you through the process of configuring your ESP32 to connect to Wi-Fi and serve a dynamic HTML page using the AsyncWebServer library. This approach is efficient for creating web-based IoT applications where you can interact with your device through a web browser.

Prerequisites

• Basic knowledge of Arduino programming.
• ESP32 development board.
• Arduino IDE installed on your computer.
• AsyncWebServer library installed in the Arduino IDE.
• Wi-Fi network credentials (SSID and password).

Parts/Tools

• ESP32 development board
• USB cable for connecting the ESP32 to your computer
• Arduino IDE
• Computer with internet access

Steps

1. Install the AsyncWebServer Library
   1. Open the Arduino IDE.
   2. Go to Sketch > Include Library > Manage Libraries.
   3. Search for AsyncWebServer.
   4. Install the library by clicking on the Install button.
2. Connect the ESP32 to Your Computer
   1. Use a USB cable to connect the ESP32 board to your computer.
   2. Select the correct board and port in the Arduino IDE:
      • Go to Tools > Board and select ESP32 Dev Module.
      • Go to Tools > Port and select the port for your ESP32.
3. Write the Code
   1. Create a new sketch in the Arduino IDE.
   2. Copy and paste the following code:

   #include <WiFi.h>
   #include <ESPAsyncWebServer.h>
   
   // Replace with your network credentials
   const char* ssid = "YOUR_SSID";
   const char* password = "YOUR_PASSWORD";
   
   AsyncWebServer server(80);
   
   void setup() {
       Serial.begin(115200);
       WiFi.begin(ssid, password);
       
       while (WiFi.status() != WL_CONNECTED) {
           delay(1000);
           Serial.println("Connecting to WiFi...");
       }
       
       Serial.println("Connected to WiFi");
       Serial.println(WiFi.localIP());
   
       server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){
           request->send(200, "text/html", "<h1>Hello, ESP32!</h1>");
       });
   
       server.begin();
   }
   
   void loop() {}
               

   3. Replace YOUR_SSID and YOUR_PASSWORD with your actual Wi-Fi credentials.
4. Upload the Code to the ESP32
   1. Click the upload button in the Arduino IDE.
   2. After the upload is complete, open the Serial Monitor (Ctrl + Shift + M).
   3. Set the baud rate to 115200.
   4. Note the IP address printed in the Serial Monitor. This is the address to access your web server.
5. Access the Dynamic HTML Page
   1. Open a web browser.
   2. Enter the IP address obtained from the Serial Monitor into the address bar.
   3. You should see a page displaying Hello, ESP32!.

Troubleshooting

• If you cannot connect to Wi-Fi:
  • Double-check your SSID and password for accuracy.
  • Ensure your ESP32 is within range of the Wi-Fi signal.
• If the page does not load:
  • Ensure the ESP32 is properly powered and connected.
  • Check the Serial Monitor for any error messages.
• If you receive a 404 error:
  • Verify that the route in the server.on() method matches the URL you are trying to access.

Conclusion

In this tutorial, you learned how to configure your ESP32 to connect to Wi-Fi and serve a dynamic HTML page using the AsyncWebServer library. This setup allows for easy interaction with your ESP32 via any web browser, paving the way for more complex web-based IoT applications.