Subhajit Das
Published © GPL3+

Smart Home With Multiple NodeMCU ESP8266 Network With Blynk

Make IoT-based Smart Home Automation using Multiple NodeMCU ESP8266 network to control all the home appliances from the pushbuttons & Blynk.

IntermediateFull instructions provided10 hours422
Smart Home With Multiple NodeMCU ESP8266 Network With Blynk

Things used in this project

Hardware components

NodeMCU ESP8266 Breakout Board
NodeMCU ESP8266 Breakout Board
×1
4-CHANNEL RELAY CONTROLLER FOR I2C
ControlEverything.com 4-CHANNEL RELAY CONTROLLER FOR I2C
×1
Pushbutton switch 12mm
SparkFun Pushbutton switch 12mm
×1

Software apps and online services

Arduino IDE
Arduino IDE
Blynk
Blynk

Hand tools and fabrication machines

Soldering iron (generic)
Soldering iron (generic)

Story

Read more

Schematics

Circuit for NodeMCU & Blynk Controlled Relay with pushbuttons

Circuit for NodeMCU & Blynk Controlled Relay with pushbuttons

Code

Code for multiple NodeMCUs controlled Relays with Blynk & Manual Switch

Arduino
Code for multiple NodeMCUs controlled Relays with Blynk & Manual Switch
/**********************************************************************************
 *  TITLE: Blynk + Manual Switch control Relays using Multiple NodeMCU (Real time feedback + no WiFi control)
 *  Click on the following links to learn more. 
 *  YouTube Video: https://youtu.be/v4MealVM5bE
 *  Related Blog : https://iotcircuithub.com/esp8266-projects/
 *  by Tech StudyCell
 *  Preferences--> Aditional boards Manager URLs : 
 *  https://dl.espressif.com/dl/package_esp32_index.json, http://arduino.esp8266.com/stable/package_esp8266com_index.json
 *  
 *  Download Board ESP8266 NodeMCU : https://github.com/esp8266/Arduino
 *  Download the libraries
 *  https://github.com/blynkkk/blynk-library/releases/download/v0.6.1/Blynk_Release_v0.6.1.zip
 **********************************************************************************/

//#define BLYNK_PRINT Serial            
#include <BlynkSimpleEsp8266.h> 

// define the GPIO connected with Relays and switches
#define RelayPin1 5  //D1
#define RelayPin2 4  //D2
#define RelayPin3 14 //D5
#define RelayPin4 12 //D6

#define SwitchPin1 10  //SD3
#define SwitchPin2 0   //D3 
#define SwitchPin3 13  //D7
#define SwitchPin4 3   //RX

#define wifiLed   16   //D0

//Change the virtual pins according the rooms
#define VPIN_BUTTON_1    V1 
#define VPIN_BUTTON_2    V2
#define VPIN_BUTTON_3    V3 
#define VPIN_BUTTON_4    V4

int toggleState_1 = 1; //Define integer to remember the toggle state for relay 1
int toggleState_2 = 1; //Define integer to remember the toggle state for relay 2
int toggleState_3 = 1; //Define integer to remember the toggle state for relay 3
int toggleState_4 = 1; //Define integer to remember the toggle state for relay 4

int wifiFlag = 0;

#define AUTH "AUTH TOKEN"                 // You should get Auth Token in the Blynk App.  
#define WIFI_SSID "Wifi Name"             //Enter Wifi Name
#define WIFI_PASS "Wifi Password"         //Enter wifi Password

BlynkTimer timer;

void relayOnOff(int relay){
    switch(relay){
      case 1: 
             if(toggleState_1 == 1){
              digitalWrite(RelayPin1, LOW); // turn on relay 1
              toggleState_1 = 0;
              Serial.println("Device1 ON");
              }
             else{
              digitalWrite(RelayPin1, HIGH); // turn off relay 1
              toggleState_1 = 1;
              Serial.println("Device1 OFF");
              }
             delay(100);
      break;
      case 2: 
             if(toggleState_2 == 1){
              digitalWrite(RelayPin2, LOW); // turn on relay 2
              toggleState_2 = 0;
              Serial.println("Device2 ON");
              }
             else{
              digitalWrite(RelayPin2, HIGH); // turn off relay 2
              toggleState_2 = 1;
              Serial.println("Device2 OFF");
              }
             delay(100);
      break;
      case 3: 
             if(toggleState_3 == 1){
              digitalWrite(RelayPin3, LOW); // turn on relay 3
              toggleState_3 = 0;
              Serial.println("Device3 ON");
              }
             else{
              digitalWrite(RelayPin3, HIGH); // turn off relay 3
              toggleState_3 = 1;
              Serial.println("Device3 OFF");
              }
             delay(100);
      break;
      case 4: 
             if(toggleState_4 == 1){
              digitalWrite(RelayPin4, LOW); // turn on relay 4
              toggleState_4 = 0;
              Serial.println("Device4 ON");
              }
             else{
              digitalWrite(RelayPin4, HIGH); // turn off relay 4
              toggleState_4 = 1;
              Serial.println("Device4 OFF");
              }
             delay(100);
      break;
      default : break;      
      }  
}

void with_internet(){
    //Manual Switch Control
    if (digitalRead(SwitchPin1) == LOW){
      delay(200);
      relayOnOff(1); 
      Blynk.virtualWrite(VPIN_BUTTON_1, toggleState_1);   // Update Button Widget  
    }
    else if (digitalRead(SwitchPin2) == LOW){
      delay(200);
      relayOnOff(2);      
      Blynk.virtualWrite(VPIN_BUTTON_2, toggleState_2);   // Update Button Widget
    }
    else if (digitalRead(SwitchPin3) == LOW){
      delay(200);
      relayOnOff(3);
      Blynk.virtualWrite(VPIN_BUTTON_3, toggleState_3);   // Update Button Widget
    }
    else if (digitalRead(SwitchPin4) == LOW){
      delay(200);
      relayOnOff(4);
      Blynk.virtualWrite(VPIN_BUTTON_4, toggleState_4);   // Update Button Widget
    }
}
void without_internet(){
    //Manual Switch Control
    if (digitalRead(SwitchPin1) == LOW){
      delay(200);
      relayOnOff(1);      
    }
    else if (digitalRead(SwitchPin2) == LOW){
      delay(200);
      relayOnOff(2);
    }
    else if (digitalRead(SwitchPin3) == LOW){
      delay(200);
      relayOnOff(3);
    }
    else if (digitalRead(SwitchPin4) == LOW){
      delay(200);
      relayOnOff(4);
    }
}

//BLYNK_CONNECTED() {
//  // Request the latest state from the server
//  Blynk.syncVirtual(VPIN_BUTTON_1);
//  Blynk.syncVirtual(VPIN_BUTTON_2);
//  Blynk.syncVirtual(VPIN_BUTTON_3);
//  Blynk.syncVirtual(VPIN_BUTTON_4);
//}

// When App button is pushed - switch the state

BLYNK_WRITE(VPIN_BUTTON_1) {
  toggleState_1 = param.asInt();
  digitalWrite(RelayPin1, toggleState_1);
}

BLYNK_WRITE(VPIN_BUTTON_2) {
  toggleState_2 = param.asInt();
  digitalWrite(RelayPin2, toggleState_2);
}

BLYNK_WRITE(VPIN_BUTTON_3) {
  toggleState_3 = param.asInt();
  digitalWrite(RelayPin3, toggleState_3);
}

BLYNK_WRITE(VPIN_BUTTON_4) {
  toggleState_4 = param.asInt();
  digitalWrite(RelayPin4, toggleState_4);
}

void checkBlynkStatus() { // called every 3 seconds by SimpleTimer

  bool isconnected = Blynk.connected();
  if (isconnected == false) {
    wifiFlag = 1;
  }
  if (isconnected == true) {
    wifiFlag = 0;
    Blynk.virtualWrite(VPIN_BUTTON_1, toggleState_1);
    Blynk.virtualWrite(VPIN_BUTTON_2, toggleState_2);
    Blynk.virtualWrite(VPIN_BUTTON_3, toggleState_3);
    Blynk.virtualWrite(VPIN_BUTTON_4, toggleState_4);
  }
}
void setup()
{
  Serial.begin(9600);

  pinMode(RelayPin1, OUTPUT);
  pinMode(RelayPin2, OUTPUT);
  pinMode(RelayPin3, OUTPUT);
  pinMode(RelayPin4, OUTPUT);

  pinMode(wifiLed, OUTPUT);

  pinMode(SwitchPin1, INPUT_PULLUP);
  pinMode(SwitchPin2, INPUT_PULLUP);
  pinMode(SwitchPin3, INPUT_PULLUP);
  pinMode(SwitchPin4, INPUT_PULLUP);

  //During Starting all Relays should TURN OFF
  digitalWrite(RelayPin1, toggleState_1);
  digitalWrite(RelayPin2, toggleState_2);
  digitalWrite(RelayPin3, toggleState_3);
  digitalWrite(RelayPin4, toggleState_4);

  digitalWrite(wifiLed, HIGH);

  WiFi.begin(WIFI_SSID, WIFI_PASS);
  timer.setInterval(3000L, checkBlynkStatus); // check if Blynk server is connected every 3 seconds
  Blynk.config(AUTH);
  delay(1000);

  Blynk.virtualWrite(VPIN_BUTTON_1, toggleState_1);
  Blynk.virtualWrite(VPIN_BUTTON_2, toggleState_2);
  Blynk.virtualWrite(VPIN_BUTTON_3, toggleState_3);
  Blynk.virtualWrite(VPIN_BUTTON_4, toggleState_4);
}

void loop()
{  
  if (WiFi.status() != WL_CONNECTED)
  {
    //Serial.println("WiFi Not Connected");
    digitalWrite(wifiLed, HIGH);
  }
  else
  {
    //+Serial.println("WiFi Connected");
    digitalWrite(wifiLed, LOW); //Turn on WiFi LED
    Blynk.run();
  }

  timer.run(); // Initiates SimpleTimer
  if (wifiFlag == 0)
    with_internet();
  else
    without_internet();
}

Credits

Subhajit Das

Subhajit Das

15 projects • 24 followers
I have studied Electrical Engineering. I do love to make different DIY electronics projects & share it on my YouTube channel Tech StudyCell.

Comments

Add projectSign up / Login