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ESP8266n based home automation project


   IOT HOME AUTOMATION USING NODE MCU                                  

                                 
In this post you will see how to make a system that lets you control your appliances using a node mcu board . Node mcu board is a development board consisting of a esp8266 wifi module along with programming circuits. you  will need following parts for this project :-

 1.NODE MCU board
2.relay module or some relays and transistors
3.matrix board
4.screw connectors or headers
5.5v power supply
6.USB cable

now follow the instructions below
1.connect your node mcu to computer and open arduino IDE
2.Now go to preferances and add this url in arduino board manager url
     http://arduino.esp8266.com/stable/package_esp8266com_index.json


3.now go to tools/boards/manage boards/ and search and add node mcu board from there

4.now selecet node mcu 1.0 12E board and upload following code to the mcu board.





// Load Wi-Fi library
#include <ESP8266WiFi.h>

// Replace with your network credentials
const char* ssid     = "kali";
const char* password = "0TSspwyV";

// 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 output5State = "off";
String output4State = "off";
String output0State = "off";
String output2State = "off";
// Assign output variables to GPIO pins
const int output5 = 5;
const int output4 = 4;
const int output0 = 0;
const int output2 = 2;
void setup() {
  Serial.begin(9600);
  // Initialize the output variables as outputs
  pinMode(output5, OUTPUT);
  pinMode(output4, OUTPUT);
   pinMode(output0, OUTPUT);
  pinMode(output2, OUTPUT);
  // Set outputs to LOW
  digitalWrite(output5, LOW);
  digitalWrite(output4, LOW);
 digitalWrite(output0, LOW);
  digitalWrite(output2, LOW);

  // 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");
              output5State = "on";
              digitalWrite(output5, HIGH);
            } else if (header.indexOf("GET /5/off") >= 0) {
              Serial.println("GPIO 5 off");
              output5State = "off";
              digitalWrite(output5, LOW);
            } else if (header.indexOf("GET /4/on") >= 0) {
              Serial.println("GPIO 4 on");
              output4State = "on";
              digitalWrite(output4, HIGH);
            } else if (header.indexOf("GET /4/off") >= 0) {
              Serial.println("GPIO 4 off");
              output4State = "off";
              digitalWrite(output4, LOW);
            }
             else if(header.indexOf("GET /0/on") >= 0) {
              Serial.println("GPIO 0 on");
              output0State = "on";
              digitalWrite(output0, HIGH);
            } else if (header.indexOf("GET /0/off") >= 0) {
              Serial.println("GPIO 0 off");
              output0State = "off";
              digitalWrite(output0, LOW);
            } else if (header.indexOf("GET /2/on") >= 0) {
              Serial.println("GPIO 2 on");
              output2State = "on";
              digitalWrite(output2, HIGH);
            } else if (header.indexOf("GET /2/off") >= 0) {
              Serial.println("GPIO 2 off");
              output2State = "off";
              digitalWrite(output2, LOW);
            }
          
            // 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 { font-family: Helvetica; display: inline-block; margin: 0px auto; text-align: center;}");
            client.println(".button { background-color: #195B6A; border: none; color: white; padding: 16px 40px;");
            client.println("text-decoration: none; font-size: 30px; margin: 2px; cursor: pointer;}");
            client.println(".button2 {background-color: #77878A;}</style></head>");
            // Web Page Heading
            client.println("<body><h1>Home Automation Server</h1>");
          
            // Display current state, and ON/OFF buttons for GPIO 5
            client.println("<p>GPIO 5 - State " + output5State + "</p>");
            // If the output5State is off, it displays the ON button     
            if (output5State=="off") {
              client.println("<p><a href=\"/5/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/5/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
             
            // Display current state, and ON/OFF buttons for GPIO 4
            client.println("<p>GPIO 4 - State " + output4State + "</p>");
            // If the output4State is off, it displays the ON button     
            if (output4State=="off") {
              client.println("<p><a href=\"/4/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/4/off\"><button class=\"button button2\">OFF</button></a></p>");
            }

            // Display current state, and ON/OFF buttons for GPIO 0
            client.println("<p>GPIO 0 - State " + output0State + "</p>");
            // If the output5State is off, it displays the ON button     
            if (output0State=="off") {
              client.println("<p><a href=\"/0/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/0/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
             
            // Display current state, and ON/OFF buttons for GPIO 4
            client.println("<p>GPIO 2 - State " + output2State + "</p>");
            // If the output4State is off, it displays the ON button     
            if (output2State=="off") {
              client.println("<p><a href=\"/2/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/2/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
            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("");
  }
}
In node mcu you can take output from following output pins

node mcu board with output pins for above code
here are some pictures of completed project


                                             fig_ complted project board
                                            fig:-interface on the web
from above system you can control four devices through internet if you want to add more devices than you need to edit ffew lines of code and add some relays and thats it .

after uploading the code open serial monitor set bud rate to 115200 and enter the ip appearing in monitor and you will see online control buttons through which you will be able to control the outputs.

before uploading code edit ssid with your wifi name and password with your wifi password.
 if you have any questions comment below or email me on anpmht@gmail.com.


                                                                                                                                       about author
                                                                                                                                     


Location: Budol, Dhulikhel 45200, Nepal

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