Serial Communication Over WiFi with ESP-01 Wifi Module As AP Station Mode

To establish serial communication over WiFi with an ESP-01 Wifi Module in Access Point (AP) station mode, you can follow these steps:

1. Connect your ESP-01 module to your computer via USB-to-Serial converter or an Arduino board, as described in the previous answer.
2. Open the Arduino IDE and create a new sketch.
3. Include the ESP8266WiFi and SoftwareSerial libraries in your sketch. The ESP8266WiFi library provides the functionality to configure the ESP-01 module as an AP station and connect it to a WiFi network. The SoftwareSerial library enables communication with the ESP-01 module over the serial port.
4. In the sketch, define the SSID and password of the WiFi network that you want the ESP-01 module to connect to. Then, create a new instance of the ESP8266WiFi class and call the begin() function to initialize the WiFi connection.
5. Set the ESP-01 module to AP station mode by sending the command “AT+CWMODE=2” over the serial port. This command sets the module to Access Point (AP) mode, which allows other devices to connect to it as a WiFi network.
6. Configure the ESP-01 module as an AP station by sending the command “AT+CWJAP=”SSID”,”password”” over the serial port. This command connects the ESP-01 module to the specified WiFi network and enables other devices to connect to it as an Access Point (AP).
7. Create a new instance of the SoftwareSerial class with the appropriate pins for your board and the ESP-01 module.
8. In the setup() function, initialize both the Serial and the SoftwareSerial ports with the appropriate baud rate (in this case, 9600).
9. In the loop() function, you can send and receive data over the WiFi network using the SoftwareSerial port to communicate with the ESP-01 module. For example, you can send a message to the ESP-01 module and receive a response using the SoftwareSerial.write() and SoftwareSerial.read() functions.

Here’s an example code to get you started:

#include <ESP8266WiFi.h>
#include <SoftwareSerial.h>

const char* ssid = "YOUR_SSID";
const char* password = "YOUR_PASSWORD";

SoftwareSerial espSerial(2, 3); // RX, TX

void setup() {
  Serial.begin(9600);
  espSerial.begin(9600);

  // Set ESP-01 module to AP station mode
  espSerial.println("AT+CWMODE=2");

  // Connect to WiFi network
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }

  // Configure ESP-01 module as an AP station
  String cmd = "AT+CWJAP=\"" + String(ssid) + "\",\"" + String(password) + "\"";
  espSerial.println(cmd);
}

void loop() {
  if (espSerial.available()) {
    Serial.write(espSerial.read());
  }
  if (Serial.available()) {
    espSerial.write(Serial.read());
  }
}

This code sets the ESP-01 module to AP station mode, connects it to the specified WiFi network, and loops through sending and receiving data between the computer and the ESP-01 module over the WiFi network using the SoftwareSerial port. Note that you may need to modify the code to suit your specific use case, such as adding error handling and message parsing.