1.  
  2. int ledPinb = 11;    // Blue LED connected to digital pin 11
  3. int ledPing = 10     // Green LED connected to digital pin 10 
  4. int ledPinr = 9;     // Red LED connected to digital pin 9
  5.  
  6. void setup()  { 
  7.   // nothing happens in setup 
  8. } 
  9.  
  10. void loop()  { 
  11.   // Green to Blue
  12.   for(int fadeValueb = 0, fadeValueg = 255, fadeValuer =0; fadeValueb <= 255, fadeValueg >= 0; fadeValueb +=5, fadeValueg -=5){
  13.     // sets the value (range from 0 to 255):
  14.     analogWrite(ledPinb, fadeValueb); analogWrite(ledPing, fadeValueg); analogWrite(ledPinr, fadeValuer);
  15.     //30 milliseconds to see the dimming effect    
  16.            delay(30);   
  17.   }
  18. // Blue to Red
  19.   for(int fadeValueg = 0, fadeValueb = 255, fadeValuer = 0; fadeValueg <= 0, fadeValueb >= 0, fadeValuer <= 255; fadeValueg +=0, fadeValueb -=5, fadeValuer +=5){
  20.     // sets the value (range from 0 to 255):
  21.     analogWrite(ledPing, fadeValueg); analogWrite(ledPinb, fadeValueb); analogWrite(ledPinr, fadeValuer);
  22.     //30 milliseconds to see the dimming effect    
  23.            delay(30);             
  24.   } 
  25.  
  26. // Red to Green
  27.   for(int fadeValueg = 0, fadeValueb = 0, fadeValuer = 255; fadeValueg <= 0, fadeValueb >= 0, fadeValuer >= 0; fadeValueg +=5, fadeValueb -=0, fadeValuer -=5){
  28.     // sets the value (range from 0 to 255):
  29.     analogWrite(ledPing, fadeValueg); analogWrite(ledPinb, fadeValueb); analogWrite(ledPinr, fadeValuer);
  30.     //30 milliseconds to see the dimming effect    
  31.            delay(30);             
  32.   } 
  33.  
  34. }
  35.  
  36. // Based on the arduino source code
  37. // Modified by Jon Mulligan