ESP32 ArduinoCore Interface – Wi-Fi

The ESP32 ArduinoCore interface for Wi-Fi provides a straightforward and flexible way to enable Wi-Fi connectivity in projects developed using the ESP32 microcontroller platform with the Arduino IDE. With this interface, developers can easily incorporate Wi-Fi functionality into their projects, enabling devices to connect to wireless networks, access the internet, and communicate with other devices over Wi-Fi.

Features and Capabilities

1. Access Point (AP) Mode: The ESP32 can act as an access point, allowing other devices to connect to it and access resources or services hosted by the ESP32.
2. Station (STA) Mode: The ESP32 can connect to existing Wi-Fi networks as a client, enabling devices to access the internet or communicate with other networked devices.
3. Soft Access Point (SoftAP) Mode: This mode enables the ESP32 to simultaneously act as both an access point and a station, allowing it to connect to an existing Wi-Fi network while also providing Wi-Fi access to other devices.
4. Wi-Fi Protected Setup (WPS): The ESP32 supports WPS, a method for easily configuring Wi-Fi network security settings without needing to enter a password manually.
5. Advanced Configuration Options: The interface provides access to advanced configuration options for fine-tuning Wi-Fi settings, such as specifying static IP addresses, setting up captive portals, and configuring Wi-Fi sleep modes to optimize power consumption.
6. Event Handling: Developers can implement event handlers to respond to Wi-Fi-related events, such as successful connections, disconnections, or errors, allowing for more robust and responsive Wi-Fi functionality.
7. Security Features: The ESP32 ArduinoCore interface supports various Wi-Fi security protocols, including WPA and WPA2, to ensure secure communication over Wi-Fi networks.

Overall, the ESP32 ArduinoCore interface for Wi-Fi simplifies the process of adding Wi-Fi connectivity to ESP32-based projects, making it easier for developers to create IoT devices, home automation systems, and other wireless applications.

Scan WiFi

Note: You can use Arduino example code instead of the below code because both are the same  (File > Example > WiFi> WiFiScan)

/* https://aruneworld.com/embedded/espressif/esp32
 * Tested By  : Arun(20170429)
 * Example Name : AEW_WiFi_Scan.ino
 *  This sketch demonstrates how to scan WiFi networks.
 *  The API is almost the same as with the WiFi Shield library,
 *  the most obvious difference being the different file you need to include:
 */
#include "WiFi.h"

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

    // Set WiFi to station mode and disconnect from an AP if it was previously connected
    WiFi.mode(WIFI_STA);
    WiFi.disconnect();
    delay(100);

    Serial.println("Setup done");
}

void loop()
{
    Serial.println("scan start");

    // WiFi.scanNetworks will return the number of networks found
    int n = WiFi.scanNetworks();
    Serial.println("scan done");
    if (n == 0) {
        Serial.println("no networks found");
    } else {
        Serial.print(n);
        Serial.println(" networks found");
        for (int i = 0; i < n; ++i) {
            // Print SSID and RSSI for each network found
            Serial.print(i + 1);
            Serial.print(": ");
            Serial.print(WiFi.SSID(i));
            Serial.print(" (");
            Serial.print(WiFi.RSSI(i));
            Serial.print(")");
            Serial.println((WiFi.encryptionType(i) == WIFI_AUTH_OPEN)?" ":"*");
            delay(10);
        }
    }
    Serial.println("");

    // Wait a bit before scanning again
    delay(5000);
}

Serial Terminal Output

scan start
scan done
5 networks found
1: ArunEworld (-34)*
2: Exuber_365 (-59)*
3: Bangalore Police (-66)*
4: Tagos-2.4 (-80)*
5: RRL_Internet (-93)*

Code Explanation

Certainly! Here’s the code with explanations provided as snippets:

#include "WiFi.h"

This line includes the WiFi library necessary for working with WiFi on the ESP32.

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

    WiFi.mode(WIFI_STA);
    WiFi.disconnect();
    delay(100);

    Serial.println("Setup done");
}

In the setup() function:

• The code initializes serial communication at a baud rate of 115200.
• The WiFi mode is set to station mode (WIFI_STA) and any previous connection is disconnected using WiFi.disconnect().
• The code adds a delay of 100 milliseconds.
• The code prints “Setup done” to the serial monitor.

void loop()
{
    Serial.println("scan start");

    int n = WiFi.scanNetworks();
    Serial.println("scan done");

    if (n == 0) {
        Serial.println("no networks found");
    } else {
        Serial.print(n);
        Serial.println(" networks found");
        for (int i = 0; i < n; ++i) {
            Serial.print(i + 1);
            Serial.print(": ");
            Serial.print(WiFi.SSID(i));
            Serial.print(" (");
            Serial.print(WiFi.RSSI(i));
            Serial.print(")");
            Serial.println((WiFi.encryptionType(i) == WIFI_AUTH_OPEN)?" ":"*");
            delay(10);
        }
    }

    Serial.println("");

    delay(5000);
}

In the loop() function:

• The code begins by printing “scan start” to the serial monitor.
• Next, the ESP32 scans for nearby WiFi networks using the WiFi.scanNetworks() function, storing the number of networks found in variable n.
• After completing the scan, the code prints “scan done” to the serial monitor.
• The code prints the number of networks found when it detects networks, followed by details of each network, including index, SSID (network name), RSSI (signal strength), and encryption type.
• If no networks are found (when n == 0), the message “no networks found” is printed.
• When networks are found, the code prints the number of networks found, followed by details of each network, including index, SSID (network name), RSSI (signal strength), and encryption type.
• Finally, the code adds a delay of 5 seconds before initiating the next scan.

These snippets provide an overview of how the code initializes WiFi and continuously scans for nearby networks, printing details to the serial monitor.