ESP32 WiFi Library –WiFiMulti.addAP

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Description

The WiFiMulti.addAP method is used to add multiple Access Points (APs). This allows the ESP32 to connect to different WiFi networks sequentially, providing a fallback mechanism if the primary network is unavailable. This method is particularly useful in IoT applications where reliable connectivity is crucial.

Syntax and Usage

The WiFiMulti.addAP method can be used in the following way:

bool addAP(const char* ssid, const char* passphrase = NULL);

Adds an AP with the specified SSID and an optional passphrase. If the network is open (no password), the passphrase can be omitted or set to NULL.

Arguments

• ssid: The SSID (name) of the Wi-Fi network. This is a required parameter.
• passphrase: The password for the Wi-Fi network. This is an optional parameter; if omitted or set to NULL, the network is assumed to be open.

Return Value

The method returns a boolean value:

• true: The AP was successfully added to the list.
• false: The AP could not be added (e.g., due to invalid parameters).

Example Codes

This code demonstrates how to use the ESP32 WiFiMulti class’s addAP() method to connect to multiple access points (APs). The addAP() method allows you to specify different WiFi networks with their SSIDs and passwords. The ESP32 will automatically try to connect to the strongest available network from the list, making it ideal for environments with varying WiFi coverage.

To use this code, replace “SSID1”, “password1”, and other placeholders with your actual WiFi network credentials. Upload the code to your ESP32 and open the Serial Monitor at 115200 baud. The code adds multiple networks using addAP(), connects to the best available one, and prints the assigned IP address once connected. Ensure the ESP32 is within range of at least one of the specified networks.

/*
 * Author: Avant Maker
 * Date: February 18, 2025
 * Version: 1.0
 * Description: This example code demonstrates how to 
 * use WiFiMulti.addAP method to add multiple APs and 
 * connect to the strongest available network.
 *
 * License: MIT 
 * 
 * Code Source: This example code is sourced from the Comprehensive 
 * Guide to the ESP32 Arduino Core Library, accessible on 
 * AvantMaker.com. For additional code examples and in-depth 
 * documentation related to the ESP32 Arduino Core Library, 
 * please visit:
 *
 * https://avantmaker.com/references/esp32-arduino-core-index/
 *
 * AvantMaker.com, your premier destination for all things 
 * DIY, AI, IoT, Smart Home, and STEM projects. We are dedicated 
 * to empowering makers,learners, and enthusiasts with the resources
 *  they need to bring their innovative ideas to life.
 */

#include <WiFi.h>
#include <WiFiMulti.h>

WiFiMulti wifiMulti;

void setup() {
    Serial.begin(115200);

    // Add multiple APs
    wifiMulti.addAP("SSID1", "password1");
    wifiMulti.addAP("SSID2", "password2");
    wifiMulti.addAP("SSID3"); // Open network

    Serial.println("Connecting...");
    while (wifiMulti.run() != WL_CONNECTED) {
        delay(1000);
        Serial.print(".");
    }
    Serial.println("\nConnected to WiFi!");
    Serial.print("IP Address: ");
    Serial.println(WiFi.localIP());
}

void loop() {
    // Your code here
}