Step 5: First IoT Project – Control LED from Browser

Now let’s host a mini web server on ESP8266 so you can control an LED.

Wiring (if using external LED):

• LED anode → D1 (GPIO5)
• LED cathode → Resistor → GND

🔌 (Or just use onboard LED at pin LED_BUILTIN).

Code: ESP8266 Web Server Example

C++

#include <ESP8266WiFi.h>

#include <ESP8266WebServer.h>

 

// WiFi config

const char* ssid = “YourWiFiName”;

const char* password = “YourWiFiPassword”;

 

ESP8266WebServer server(80);  // Create a web server at port 80

int ledPin = D1;

 

void handleRoot() {

server.send(200, “text/html”,

“<h1>ESP8266 LED Control</h1> \

<p><a href=\”/on\”>Turn ON</a></p> \

<p><a href=\”/off\”>Turn OFF</a></p>”);

}

 

void handleOn() {

digitalWrite(ledPin, HIGH);

server.send(200, “text/html”, “LED is ON <br><a href=\”/\”>Back</a>”);

}

 

void handleOff() {

digitalWrite(ledPin, LOW);

server.send(200, “text/html”, “LED is OFF <br><a href=\”/\”>Back</a>”);

}

 

void setup() {

pinMode(ledPin, OUTPUT);

digitalWrite(ledPin, LOW);

 

Serial.begin(115200);

WiFi.begin(ssid, password);

 

Serial.print(“Connecting”);

while (WiFi.status() != WL_CONNECTED) {

delay(500); Serial.print(“.”);

}

Serial.print(“\nConnected! IP: “);

Serial.println(WiFi.localIP());

 

server.on(“/”, handleRoot);

server.on(“/on”, handleOn);

server.on(“/off”, handleOff);

server.begin();

Serial.println(“Web server started.”);

}

 

void loop() {

server.handleClient();

}