Introduction: Blu - LED's

About: ! Error 404 !

There are so many instructables on the web , but this is the most simplest and easiest to upgrade further !!


  • Arduino UNO | Amazon
  • Bluetooth Module | Amazon
  • LED's | Amazon
  • Arduino IDE
  • A smart phone or your laptop

Step 1: Setting Up Circuit Connections !!

  • Set up the led connection as shown in diagram !!
  • Skip to step 3 and come back again !
  • Connect Bluetooth after uploading the program !!

NOTE : Please connect the Bluetooth module as directed :

RX of Bluetooth module goes to TX of arduino board!

TX of Bluetooth module goes to RX of arduino board!

You are almost done !!

Download the app , to control your project !!

Connect to the app and bingo , you are done !!

Step 2: Copy the Program Here !!

/* ©Compiler Bro's  */
Intially define the state to be zero!
int state= 0;
voidsetup(){// put your setup code here, to run once://Set up a communication between arduino and your systemSerial.begin(9600);Serial.println("Connected!!");pinMode(ledPin,OUTPUT);digitalWrite(ledPin,LOW);}voidloop(){// put your main code here, to run repeatedly:if(Serial.available()>0){;}if(state=='A'){digitalWrite(ledPin,LOW);Serial.println("LED : OFF");state=0;}elseif(state=='B'){digitalWrite(ledPin,HIGH);Serial.println(" LED : ON");state=0;}}