Home automation using Arduino

Circuit Diagram:

Arduino code:

#define fan 2

#define light 3

void setup() {

  // put your setup code here, to run once:

  Serial.begin(9600);

  pinMode(fan, OUTPUT);

  pinMode(light, OUTPUT);

}

void loop() {

  // put your main code here, to run repeatedly:

  if(Serial.available() == 1)

  {

    String val = Serial.readString();

    Serial.println(val);

    if(val == "fan on")

    {

      digitalWrite(fan, HIGH);

    }

    if(val == "fan off")

    {

      digitalWrite(fan, LOW);

    }

    if(val == "lights on")

    {

      digitalWrite(lights, HIGH);

    }

    if(val == "lights off")

    {

      digitalWrite(light, LOW);

    }

    if(val == "all on")

    {

      digitalWrite(fan, HIGH);

      digitalWrite(light, HIGH);

    }

    if(val == "all off")

    {

      digitalWrite(light, LOW);

      digitalWrite(fan, LOW);

    }

  }

}