Hello guys, In this post we learn How to control led using web server like chrome,safari etc.. using nodemcu /esp8266 board
Let start it :-
*Parts list
1.Nodemcu/esp8266
2.5mm 3v led
*Schematics and diagram
-do all the connection according to this diagram
*Coding
-Copy The following code in ardunio ide
/*********
-Tech Gyan Creative
Complete project details at https://techgyancreative.blogspot.com/2021/08/nodemcu-webserver.html
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
*********/
// Import required libraries
#include <ESP8266WiFi.h>
// Replace with your network credentials
const char* ssid = "WiFi name"; // Input your wifi network name
const char* password = "WiFi password"; // Input your wifi password
// Set web server port number to 80
WiFiServer server(80);
// Variable to store the HTTP request
String header;
// Auxiliar variables to store the current output state
String relay1State = "off";
String relay2State = "off";
String relay3State = "off";
String relay4State = "off";
// Assign output variables to GPIO pins
const int relay1 = 5; // GPIO5 D1
const int relay2 = 4; // GPIO4 D2
const int relay3 = 0; // GPIO0 D3
const int relay4 = 2; // GPIO2 D4
void setup() {
Serial.begin(115200);
// Initialize the output variables as outputs
pinMode(relay1, OUTPUT);
pinMode(relay2, OUTPUT);
pinMode(relay3, OUTPUT);
pinMode(relay4, OUTPUT);
// Set outputs to HIGH. relay active LOW
digitalWrite(relay1, HIGH);
digitalWrite(relay2, HIGH);
digitalWrite(relay3, HIGH);
digitalWrite(relay4, HIGH);
// Connect to Wi-Fi network with SSID and password
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
// Print local IP address and start web server
Serial.println("");
Serial.println("WiFi connected.");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
server.begin();
}
void loop() {
WiFiClient client = server.available(); // Listen for incoming clients
if (client) { // If a new client connects,
Serial.println("New Client."); // print a message out in the serial port
String currentLine = ""; // make a String to hold incoming data from the client
while (client.connected()) { // loop while the client's connected
if (client.available()) { // if there's bytes to read from the client,
char c = client.read(); // read a byte, then
Serial.write(c); // print it out the serial monitor
header += c;
if (c == 'n') { // if the byte is a newline character
// if the current line is blank, you got two newline characters in a row.
// that's the end of the client HTTP request, so send a response:
if (currentLine.length() == 0) {
// HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
// and a content-type so the client knows what's coming, then a blank line:
client.println("HTTP/1.1 200 OK");
client.println("Content-type:text/html");
client.println("Connection: close");
client.println();
// turns the GPIOs on and off
if (header.indexOf("GET /5/on") >= 0)
{
Serial.println("GPIO 5 on");
relay1State = "on";
digitalWrite(relay1, LOW);
}
else if (header.indexOf("GET /5/off") >= 0)
{
Serial.println("GPIO 5 off");
relay1State = "off";
digitalWrite(relay1, HIGH);
}
else if (header.indexOf("GET /4/on") >= 0) {
Serial.println("GPIO 4 on");
relay2State = "on";
digitalWrite(relay2, LOW);
}
else if (header.indexOf("GET /4/off") >= 0) {
Serial.println("GPIO 4 off");
relay2State = "off";
digitalWrite(relay2, HIGH);
}
else if (header.indexOf("GET /0/on") >= 0)
{
Serial.println("GPIO 0 on");
relay3State = "on";
digitalWrite(relay3, LOW);
}
else if (header.indexOf("GET /0/off") >= 0)
{
Serial.println("GPIO 0 off");
relay3State = "off";
digitalWrite(relay3, HIGH);
}
else if (header.indexOf("GET /2/on") >= 0) {
Serial.println("GPIO 2 on");
relay4State = "on";
digitalWrite(relay4, LOW);
}
else if (header.indexOf("GET /2/off") >= 0) {
Serial.println("GPIO 2 off");
relay4State = "off";
digitalWrite(relay4, HIGH);
}
// Display the HTML web page
client.println("<!DOCTYPE html><html>");
client.println("<head><meta name="viewport" content="width=device-width, initial-scale=1">");
//client.println("<link rel="icon" href="data:,">");
// CSS to style the on/off buttons
// Feel free to change the background-color and font-size attributes to fit your preferences
client.println("<style>html, body { font-family: Helvetica; display: block; margin: 0px auto; text-align: center;}");
client.println(".button { background-color: #209e48; border: none; color: white; padding: 12px 24px;");
client.println("text-decoration: none; font-size: 20px; margin: 2px; cursor: pointer;}");
client.println(".button2 {background-color: #c20a0a;}");
client.println(".textbox {width: 80px; border: 1px solid #333; padding: 16px 20px 0px 24px; background-image: linear-gradient(180deg, #fff, #ddd 40%, #ccc);}");
client.println(".mytext {font-size: 16px; font-weight:bold; font-family:Arial ; text-align: justify;}");
client.println("#container {width: 100%; height: 100%; margin-left: 5px; margin-top: 20px; padding: 10px; display: -webkit-flex; -webkit-justify-content: center; display: flex; justify-content: center;} ");
client.println("</style></head>");
// Web Page Heading
client.println("<body><h1>NodeMCU Web Server Relay Control</h1>");
// Display current state, and ON/OFF buttons for GPIO 5
client.println("<div id="container">");
client.println("<p><div class="textbox mytext">Led 1 </div> ");
// If the relay1State is off, it displays the ON button
if (relay1State == "off") {
client.println("<a href="/5/on"><button class="button">OFF</button></a></p>");
} else {
client.println("<a href="/5/off"><button class="button button2">ON</button></a></p>");
}
client.println("</div>");
// Display current state, and ON/OFF buttons for GPIO 4
client.println("<div id="container">");
client.println("<p><div class="textbox mytext">Led 2 </div> ");
// If the relay2State is off, it displays the ON button
if (relay2State == "off") {
client.println("<a href="/4/on"><button class="button">OFF</button></a></p>");
} else {
client.println("<a href="/4/off"><button class="button button2">ON</button></a></p>");
}
client.println("</div>");
// Display current state, and ON/OFF buttons for GPIO 0
client.println("<div id="container">");
client.println("<p><div class="textbox mytext">Led 3 </div>");
// If the relay1State is off, it displays the ON button
if (relay3State == "off") {
client.println("<a href="/0/on"><button class="button">OFF</button></a></p>");
} else {
client.println("<a href="/0/off"><button class="button button2">ON</button></a></p>");
}
client.println("</div>");
// Display current state, and ON/OFF buttons for GPIO 2
client.println("<div id="container">");
client.println("<p><div class="textbox mytext">Led 4 </div>");
// If the relay2State is off, it displays the ON button
if (relay4State == "off") {
client.println("<a href="/2/on"><button class="button">OFF</button></a></p>");
} else {
client.println("<a href="/2/off"><button class="button button2">ON</button></a></p>");
}
client.println("</div>");
client.println("</body></html>");
// The HTTP response ends with another blank line
client.println();
// Break out of the while loop
break;
} else { // if you got a newline, then clear currentLine
currentLine = "";
}
} else if (c != 'r') { // if you got anything else but a carriage return character,
currentLine += c; // add it to the end of the currentLine
}
}
}
// Clear the header variable
header = "";
// Close the connection
client.stop();
Serial.println("Client disconnected.");
Serial.println("");
}
}-choose your com port and board
-type your ssid and password
-upload the code
*How to control led
-connect the nodemcu with your hotspot
-open any search engine and type this url-" 192.168.1.10/4/off "
-then website is open then you control your led
