#include WiFiServer server(80); //Initialize the server on Port 80 //#define LED_PIN D4. int LED_PIN = D0; void setup() { WiFi.mode(WIFI_AP); //Our ESP8266-12E is an AccessPoint WiFi.softAP("Hello_IoT", "ashwins12345678"); // Provide the (SSID, password); . server.begin(); // Start the HTTP Server // Looking under the hood Serial.begin(115200); //Start communication between the ESP8266-12E and the monitor window IPAddress HTTPS_ServerIP = WiFi.softAPIP(); // Obtain the IP of the Server Serial.print("Server IP is: "); // Print the IP to the monitor window Serial.println(HTTPS_ServerIP); pinMode(LED_PIN, OUTPUT); // D4is an OUTPUT pin; digitalWrite(LED_PIN, LOW); //Initial state is ON } void loop() { WiFiClient client = server.available(); if (!client) { return; } //Looking under the hood Serial.println("connected :)"); //Read what the browser has sent into a String class and print the request to the monitor String request = client.readStringUntil('\r'); //Looking under the hood Serial.println(request); if (request.indexOf("/OFF") != -1) { digitalWrite(LED_PIN, HIGH); } else if (request.indexOf("/ON") != -1) { digitalWrite(LED_PIN, LOW); } // Prepare the HTML document to respond and add buttons: String s = "HTTP/1.1 200 OK\r\n"; s += "Content-Type: text/html\r\n\r\n"; s += "\r\n\r\n"; s += ""; s += "

"; s += "

"; s += "

"; s += "
"; s += "

"; s += ""; s += ""; s += "\n"; //Serve the HTML document to the browser. client.flush (); //clear previous info in the stream client.print (s); // Send the response to the client delay(1); Serial.println("Client disonnected" ); //Looking under the hood) }