Controlling RGB LED over serial

Other Hardware LEDs and Multiplexing
1

Hi

I'm trying to control an common anode RGB led using this code:

const int RED = 6;
const int GREEN = 5;
const int BLUE = 3;

int REDvalue = 0;

void setup()
{
  pinMode(RED, OUTPUT);
  pinMode(GREEN, OUTPUT);
  pinMode(BLUE, OUTPUT);
  
  Serial.begin(9600);
}

void loop(){
  if (Serial.available() > 0) {
    int REDvalue = Serial.read();
    
    switch (REDvalue) {
      case 'a':
        digitalWrite(RED, LOW);
        break;
    
    default:
    for (int RED = 6; ;) {
      digitalWrite(RED, HIGH);
    }
   }
 }
}

But when I write a in the serial monitor and press send nothing happens.

2

Did you select "No line ending" in Serial Monitor? If not, your 'a' will turn off the red LED and the line ending will immediately turn it back on.

3

Yes it's selected.

4

For some reason I can turn it off now... Which as I see it should be the opposed of what should happen. But I can't turn it back on.

5

This 'for' loop does nothing at all which might explain why you can't turn the light back on.

    for (int RED = 6; ;) {
      digitalWrite(RED, HIGH);
    }

Try it this way instead:

      digitalWrite(RED, HIGH);
6

I've asked for help for my entire project in this post:
http://arduino.cc/forum/index.php/topic,96268.0.html

Any help would be appreciated.

7

I've asked for help for my entire project in this post:

So how does the last comment:-

Ignore the question. Figured it all out a different way around.

Square with this?

8

Thank you. I had not come across that site and it helped a lot. You were right that I Led Light Accessories really needed to see how diodes worked and when I saw that understanding the LED was easy.