「arduino」用3色LED模組做七色彩虹燈

之前有一篇寫了用3色LED模組做呼吸燈，這篇來發出彩虹的顏色好了。

首先我們來找出彩虹顏色的R，G，B值，在wiki上有前輩己經將顏色整理好。

圖片來源：
https://zh.wikipedia.org/wiki/%E5%BD%A9%E8%99%B9


接下來我們開始寫程式

 int redpin = 11; //select the pin for the red LED   
 int bluepin =10; // select the pin for the blue LED   
 int greenpin =9;// select the pin for the green LED  
 int val;  
 void setup() {  
 pinMode(redpin, OUTPUT);   
 pinMode(bluepin, OUTPUT);   
 pinMode(greenpin, OUTPUT);   
 off();  
 }  
 void loop()  
 {  
  ledbreathe(255,0,0);  
  ledbreathe(255,165,0);  
  ledbreathe(255,255,0);  
  ledbreathe(0,255,0);  
  ledbreathe(0,0,255);  
  ledbreathe(43,0,255);  
  ledbreathe(87,0,255);  
 }  
 void off()  
 {  
  analogWrite(redpin,255);  
  analogWrite(bluepin,255);  
  analogWrite(greenpin,255);   
 }  
 void ledbreathe(int r,int g, int b)  
 {  
   analogWrite(redpin, 255-r);   
   analogWrite(greenpin, 255-g);   
   analogWrite(bluepin, 255-b);   
   delay(1000);   
 }  

成果影片