Common Anode RGB LED

1// LEDs must be connected to arduino PWM pins - see board pinout
2#define
3  RED  6   // pin that red led is connected to    
4#define GREEN  5 // pin that
5  green led is connected to     
6#define BLUE  3  // pin that blue led is connected
7  to    
8#define DELAY  20  // internal delay in ms
9
10void setup() { 
11
12  // LED connection pins to be set as an output
13  pinMode(RED, OUTPUT);
14  pinMode(GREEN,
15  OUTPUT);
16  pinMode(BLUE, OUTPUT);
17}
18
19void loop() {
20  // fade from
21  red to green
22  for(int i=0; i<255; i++) {
23    analogWrite(RED, i); // red
24  initially ON
25    analogWrite(GREEN, 255-i); // green initially OFF
26    analogWrite(BLUE,
27  255); // blue OFF
28    delay(DELAY); // wait before next transition
29  }
30
31
32  // fade from green to blue
33  for(int i=0; i<255; i++) {
34    analogWrite(RED,
35  255); // red OFF
36    analogWrite(GREEN, i); // green initially ON
37    analogWrite(BLUE,
38  255-i); // blue initially OFF
39    delay(DELAY);
40  }
41
42  // fade from
43  blue to red
44  for(int i=0; i<255; i++) {
45    analogWrite(RED, 255-i); // red
46  initially OFF
47    analogWrite(GREEN, 255); // green OFF
48    analogWrite(BLUE,
49  i); // blue initially ON
50    delay(DELAY);
51  }
52}
53