IoT Based Home Automation With Blynk and NodeMCU

/**********************************************************************************
 *  TITLE: Blynk Home Automation with Physical Buttons and Tempareture and Light control Smart Relay V4 (OLED 0.96" I2C)
 *  Click on the following links to learn more. 
 *  YouTube Video: https://youtu.be/rRUUYXzJ4ZQ
 *  Related Blog : https://easyelectronicsproject.com/esp32-projects/
 *  by Tech StudyCell
 *  Download the libraries
 *  https://github.com/blynkkk/blynk-library/releases/download/v0.6.1/Blynk_Release_v0.6.1.zip
 *  https://github.com/adafruit/DHT-sensor-library
 *  https://github.com/adafruit/Adafruit_SSD1306
 **********************************************************************************/

#define BLYNK_PRINT Serial            
#include <BlynkSimpleEsp8266.h> 
#include <DHT.h>                
#include <Adafruit_SSD1306.h>  

void checkPhysicalButton();

int toggleState_1 = 0;
int pushButton1State = LOW;

int toggleState_2 = 0;
int pushButton2State = LOW;

float temperature1 = 0;
float humidity1   = 0;
int   ldrVal;
int   switchMode = 0;

//Set values for Auto Control Mode
const float maxTemp = 30.5;
const float minTemp = 24.8;

const int maxLight = 1000;
const int minLight = 200;

#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


#define PUSH_BUTTON_CMODE  15 //D8
#define LDR_PIN            A0 //A0
#define DHTPIN             10 //SD3  pin connected with DHT

#define RELAY_PIN_1      14   //D5
#define RELAY_PIN_2      12   //D6

#define PUSH_BUTTON_1    16   //D0
#define PUSH_BUTTON_2    13   //D7

#define VPIN_BUTTON_1    V1 
#define VPIN_BUTTON_2    V2
#define VPIN_BUTTON_C    V3

#define VPIN_HUMIDITY    V5
#define VPIN_TEMPERATURE V6

// Uncomment whatever type you're using!
#define DHTTYPE DHT11     // DHT 11
//#define DHTTYPE DHT22   // DHT 22, AM2302, AM2321
//#define DHTTYPE DHT21   // DHT 21, AM2301

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 32 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

DHT dht(DHTPIN, DHTTYPE);
BlynkTimer timer;

void changeMode(){      
  delay(200);
  if (switchMode == 0){
    switchMode = 1;
  }
  else if (switchMode == 1) {
    switchMode = 0;
  }
  display.clearDisplay();
  display.setCursor(5,2);
  display.print("Set Mode: ");
  display.println();
  display.drawLine(0,18, display.width()-1,18, WHITE);
  display.setCursor(15,24);
  display.print(modeDecode(switchMode));     
  display.display();
  delay(500);
  Blynk.virtualWrite(VPIN_BUTTON_C, switchMode);
  //display.clearDisplay();
}

void relayOnOff(int relay){

    switch(relay){
      case 1: 
             if(toggleState_1 == 0){
              digitalWrite(RELAY_PIN_1, HIGH); // turn on relay 1
              toggleState_1 = 1;
              }
             else{
              digitalWrite(RELAY_PIN_1, LOW); // turn off relay 1
              toggleState_1 = 0;
              }
             delay(100);
      break;
      case 2: 
             if(toggleState_2 == 0){
              digitalWrite(RELAY_PIN_2, HIGH); // turn on relay 2
              toggleState_2 = 1;
              }
             else{
              digitalWrite(RELAY_PIN_2, LOW); // turn off relay 2
              toggleState_2 = 0;
              }
             delay(100);
      break;
      default : break;      
      }
  
}
String modeDecode(int count){
  if (count == 0){
    return " Manual Mode ";
  }
  else if (count == 1){
    return " Auto Mode ";
  }
}

void displayData(){
  display.clearDisplay();
  display.setTextSize(1);
  display.setCursor(8,2);
  display.print(temperature1);
  display.print(" ");
  display.print("C    ");
  display.print(humidity1); // display humidity
  display.print(" %");
  
  display.drawLine(0,18, display.width()-1,18, WHITE);
   
  display.setCursor(15,24);
  display.print(modeDecode(switchMode));   
  display.display();

  Serial.print(F("Temperature: "));
  Serial.print(temperature1);
  Serial.print("   ");
  Serial.print(F("humidity: "));
  Serial.print(humidity1);
  Serial.print("   ");
  Serial.println(ldrVal); 
  Serial.println("");
}

void readSensor(){
    
  ldrVal = analogRead(LDR_PIN);
  
  float h = dht.readHumidity();
  float t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit
  
  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }
  else {
    humidity1 = h;
    temperature1 = t;
  }  
}

void sendSensor()
{
  readSensor();
  // You can send any value at any time.
  // Please don't send more that 10 values per second.
  Blynk.virtualWrite(VPIN_HUMIDITY, humidity1);
  Blynk.virtualWrite(VPIN_TEMPERATURE, temperature1);
}

BLYNK_CONNECTED() {

  // Request the latest state from the server

  Blynk.syncVirtual(VPIN_BUTTON_1);
  Blynk.syncVirtual(VPIN_BUTTON_2);
  Blynk.syncVirtual(VPIN_BUTTON_C);
}

// When App button is pushed - switch the state

BLYNK_WRITE(VPIN_BUTTON_1) {
  toggleState_1 = param.asInt();
  digitalWrite(RELAY_PIN_1, toggleState_1);
}

BLYNK_WRITE(VPIN_BUTTON_2) {
  toggleState_2 = param.asInt();
  digitalWrite(RELAY_PIN_2, toggleState_2);
}

BLYNK_WRITE(VPIN_BUTTON_C) {
  switchMode = param.asInt();
}

void checkPhysicalButton()
{
  if (digitalRead(PUSH_BUTTON_1) == HIGH) {
      relayOnOff(1);
      // Update Button Widget
      Blynk.virtualWrite(VPIN_BUTTON_1, toggleState_1);
    }
  if (digitalRead(PUSH_BUTTON_2) == HIGH) {
      relayOnOff(2);
      // Update Button Widget
      Blynk.virtualWrite(VPIN_BUTTON_2, toggleState_2);
    }
}

void setup()
{
  Serial.begin(9600);
  
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  delay(1000);  
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.clearDisplay();

  pinMode(RELAY_PIN_1, OUTPUT);
  pinMode(PUSH_BUTTON_1, INPUT);
  digitalWrite(RELAY_PIN_1, toggleState_1);

  pinMode(RELAY_PIN_2, OUTPUT);
  pinMode(PUSH_BUTTON_2, INPUT);
  digitalWrite(RELAY_PIN_2, toggleState_2);

  Blynk.begin(AUTH, WIFI_SSID, WIFI_PASS);  
  // Setup a function to be called every 500 ms
  timer.setInterval(500L, checkPhysicalButton);
  
  dht.begin();
  // Setup a function to be called every second
  timer.setInterval(1000L, sendSensor);
  // Setup a function to be called every 2 second
  timer.setInterval(2000L, displayData);
}

void loop()
{
  if (digitalRead(PUSH_BUTTON_CMODE) == HIGH){
    changeMode();
  }   
  else{    
    if(switchMode == 1){ //if Auto Mode
      //DHT11 control Relay 1
      if(temperature1 > maxTemp){
        if(toggleState_1 == 0){
          digitalWrite(RELAY_PIN_1, HIGH); // turn ON relay 1
          toggleState_1 = 1;
          // Update Button Widget
          Blynk.virtualWrite(VPIN_BUTTON_1, toggleState_1);
        }
      }
      else if (temperature1 < minTemp){
        if(toggleState_1 == 1){
           digitalWrite(RELAY_PIN_1, LOW); // turn OFF relay 1
           toggleState_1 = 0;
           // Update Button Widget
           Blynk.virtualWrite(VPIN_BUTTON_1, toggleState_1);
          }
      }
      //LDR control Relay 2
      if( ldrVal < minLight){
        if(toggleState_2 == 0){
          digitalWrite(RELAY_PIN_2, HIGH); // turn ON relay 2
          toggleState_2 = 1;
          // Update Button Widget
          Blynk.virtualWrite(VPIN_BUTTON_2, toggleState_2);
        }
      }
      else if (ldrVal > maxLight){
        if(toggleState_2 == 1){
           digitalWrite(RELAY_PIN_2, LOW); // turn OFF relay 2
           toggleState_2 = 0;
           // Update Button Widget
           Blynk.virtualWrite(VPIN_BUTTON_2, toggleState_2);
          }
      } 
    }
    timer.run();
    Blynk.run();
  }
}