Interact and control a LED using the Serial monitor

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1

Hello, I want to control a LED, set it to either HIGH or LOW, by sending values through the serial monitor.

Here is one example of something similar, but I dont know what the Arduino code he uses looks like:
http://www.raspberrypi.org/phpBB3/viewtopic.php?f=32&t=37469

I tried with this code, but it does not work:

const int ledPin     = 9;
const int ledPin2   = 10;

void setup(){
  Serial.begin(9600);   
 
} 

void loop () {

  
     if (Serial.available()>0) {
      //int d = 0;
      int d= Serial.read();
            if ( d == 10 )
            {
              digitalWrite(ledPin, HIGH);         
              digitalWrite(ledPin2, HIGH);
            }
            else if ( d == 20 )
            {
              digitalWrite(ledPin, LOW);
              digitalWrite(ledPin2, LOW);
            }
            
          }
}

I simply plugg the Arduino into my computer, open the serial monitor and put "1" into the send text field and send it. RX LED on the Arduino flashes when I do this, but the LED does not go on. Anybody know what im doing wrong here?

2

The serial monitor sends code in ASCII, so when you type 1 it actually sends a value of 49.
Look at the example in the arduino IDE for this under serial communication.

3

Thank you!