我是基于arduino UNO R3套件来实现的RGB三色灯案例。在这整套的套件中，备有RGB三色灯集成器件。

关于RGB三色灯的电路原理，各位直接在网上就可以搜索到，这里就不过多赘述。接下来就是关于RGB三色灯的实例。程序实例和端口请根据实际情况进行调整。

RGB三色灯——流水灯效果：

#define RED   12
#define GREEN 8
#define BLUE  7
void red(void);
void green(void);
void blue(void);
void setup() {
  // put your setup code here, to run once:
  pinMode(RED, OUTPUT);
  pinMode(GREEN, OUTPUT); 
  pinMode(BLUE, OUTPUT);
  digitalWrite(RED, LOW);
  digitalWrite(RED, LOW);
  digitalWrite(RED, LOW);
}
void loop() {
  // put your main code here, to run repeatedly:
  red();
  delay(1000);
  green();
  delay(1000);
  blue();
  delay(1000);
}
void red(void)
{
  digitalWrite(RED, HIGH);
  digitalWrite(GREEN, LOW);
  digitalWrite(BLUE, LOW);
}
void green(void)
{
  digitalWrite(RED, LOW);
  digitalWrite(GREEN, HIGH);
  digitalWrite(BLUE, LOW);
}
void blue(void)
{
  digitalWrite(RED, LOW);
  digitalWrite(GREEN, LOW);
  digitalWrite(BLUE, HIGH);
}

RGB三色灯——呼吸灯效果：

#define LED_red   11
#define LED_green 10
#define LED_blue  9
void breath(int pin);
void setup() {
  // put your setup code here, to run once:
  pinMode(LED_red, OUTPUT);
  pinMode(LED_green, OUTPUT);
  pinMode(LED_blue, OUTPUT);
}
void loop() {
  // put your main code here, to run repeatedly:
  breath(LED_red);
  breath(LED_green);
  breath(LED_blue);
}
void breath(int pin)
{
  for(int i = 0; i <= 255; i++)
  {
    analogWrite(pin, i);
    delay(5);
  }
  for(int i = 255; i >= 0; i--)
  {
    analogWrite(pin, i);
    delay(5);
  }
  delay(100);
}

这里要提醒一下各位：在Arduino UNO板上，有pwm输出口，需要各位注意看，并且在这里我是用到了analogWrite(int pin, int value)函数，是arduino函数库中专门用来pwm调试输出的。