LEDサイリウムを作った時にArduinoに書き込んだコード。 記事：http://make-audio.blogspot.jp/2011/08/led.html

led_cyrium.ino

#define redLedPin 3
#define greenLedPin 5
#define blueLedPin 9
#define switchPin 2

int mode = 2;
int colorMax = 9;
int colorArray[][3]={{255,0,2},
                    {220,200,0},
                    {0,255,0},
                    {0,255,200},
                    {0,0,255},
                    {170,0,255},
                    {150,255,200},
                    {255,150,10},
                    {255,80,70}};
int i = 0;
int modeMax = colorMax + mode;

void setup(){
  pinMode(switchPin,INPUT);
}

void loop(){
  if(digitalRead(switchPin)==HIGH){
    upCount();
    delay(300);
  }
  if(i < colorMax){
    color(i);
  }else if(i == colorMax){
    colorChange();
  }else if(i == colorMax + 1){
    color(random(0,colorMax));
  }
    delay(100);
}

void upCount(){
    i++;
    if(i >= modeMax){i=0;}
}

void color(int num){
  analogWrite(redLedPin,colorArray[num][0]);
  analogWrite(greenLedPin,colorArray[num][1]);
  analogWrite(blueLedPin,colorArray[num][2]);
}

void colorChange(){
  static int red = 250;
  static int green = 0;
  static int blue = 0;
  
  if(red > 0 && blue == 0){
    red -= 10;
    green += 10;
  }else if(green > 0){
    green -= 10;
    blue += 10;
  }else{
    blue -=10;
    red +=10;
  }
  
  analogWrite(redLedPin,red);
  analogWrite(greenLedPin,green);
  analogWrite(blueLedPin,blue);
}