Circuit

Download Proteus simulation file.

Arduino Codes (Serial Communication in between two Arduino Nano)

//Transmitter : (using Hardware Serial)

//(Program downloading may be affected if any device connected with the Tx Rx pins as is being used for programming pins)

// Arduino Serial Example #1 Remote Control Blink - Master

boolean buttonSwitch1 = 14; 

boolean buttonSwitch2 = 15; 

boolean buttonState1 = false;

boolean buttonState2 = false;

boolean buttonState3 = false;

 boolean buttonSwitch1_State_old = false;

boolean buttonSwitch2_State_old = false; 

void setup() {

     pinMode( buttonSwitch1, INPUT);

    pinMode( buttonSwitch2, INPUT);

    Serial.begin(9600);  

    // wait for the serial port to connect. Required for Leonardo/Micro native USB port only

    while (!Serial) {  ;  }

    Serial.println("Starting Power Line Communication");

}

void loop() {

  // simple debounce

  buttonState1 = digitalRead(buttonSwitch1); delay(1);

  buttonState2 = digitalRead(buttonSwitch1); delay(1);

  buttonState3 = digitalRead(buttonSwitch1); delay(1);

  if ( (buttonState1 == buttonState2) && (buttonState1 == buttonState3) )  {

     // has the button switch state changed?

     if (buttonState1 != buttonSwitch1_State_old)  {

        buttonSwitch1_State_old = buttonState1;

        if (buttonSwitch1_State_old == HIGH) { Serial.print(1);}  else  { Serial.print(0);}

     }

  }

  buttonState1 = digitalRead(buttonSwitch2); delay(1);

  buttonState2 = digitalRead(buttonSwitch2); delay(1);

  buttonState3 = digitalRead(buttonSwitch2); delay(1);

  if ( (buttonState1 == buttonState2) && (buttonState1 == buttonState3) ) {

     // has the button switch state changed?

     if (buttonState1 != buttonSwitch2_State_old) {

        buttonSwitch2_State_old = buttonState1;

        if (buttonSwitch2_State_old == HIGH) { Serial.print(3);} else { Serial.print(2);}

     }

  }

 }

//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++//

//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++//

// Reciver Code

char c  = ' ';

byte LED1 = 2;

byte LED2 = 3;

byte Relay1 = 4;

byte Relay2 = 5; 

void setup() {

   pinMode(LED1, OUTPUT);

   pinMode(LED2, OUTPUT);

   pinMode(Relay1, OUTPUT);

   pinMode(Relay2, OUTPUT);

    Serial.begin(9600);

   Serial.println("START");

   digitalWrite(LED1, HIGH);

   delay(1000);

   digitalWrite(LED1, LOW);

}

void loop(){

   if(Serial.available())  {

      char c = Serial.read();

      if (c=='0') { digitalWrite(LED1, LOW); digitalWrite(Relay1, HIGH);}

      if (c=='1') { digitalWrite(LED1, HIGH); digitalWrite(Relay1, LOW);}

      if (c=='2') { digitalWrite(LED2, LOW); digitalWrite(Relay2, HIGH); }

      if (c=='3') { digitalWrite(LED2, HIGH); digitalWrite(Relay2, LOW); }

      Serial.println(c);

   }

 }