無法切換到改變LED顏色，只是循環所有顏色，無論開關是否按下

Question

我想通過本教程http://lilypadarduino.org/?page_id=216來學習如何在Arduino上做基本的事情。我想編寫一個程序，讓我用一個開關控制一個3色LED，每次按下開關時，我都希望LED從紅色變成綠色變成藍色。從我所瞭解的循環方法應該一遍又一遍地運行，應該測試以查看是否按下了開關。如果它被按下，那麼它應該增加一個計數器，直到它變爲2（藍色）並且計數器被重置。它將顏色從紅色變爲綠色，而不是當我按下開關時，它只是循環切換，就像開關總是按下一樣。我的代碼如下。

int ledPin = 13; // LED is connected to digital pin 13 
int redPin = 11; // R petal on RGB LED module connected to digital pin 11 
int greenPin = 9; // G petal on RGB LED module connected to digital pin 9 
int bluePin = 10; // B petal on RGB LED module connected to digital pin 10 
int switchValue; 
int switchPin = 2; 
int count = 0;   
int red = 255;   //red value, initially set at 255 
int blue = 0;   //blue value, initially set at 0 

void setup()  
{  
    pinMode(ledPin, OUTPUT); // sets the ledPin to be an output 
    pinMode(redPin, OUTPUT); // sets the redPin to be an output 
    pinMode(greenPin, OUTPUT); // sets the greenPin to be an output 
    pinMode(bluePin, OUTPUT); // sets the bluePin to be an output 
    //redtoblue(); 
}  

void loop() // run over and over again 
{  
    if(switchValue == LOW){ 
    if (count == 0){ 
     color(255, 0, 0); // turn the RGB LED red 
     delay(1000); // delay for 1 second 
     count += 1; //increment the count 
    } 
    else if (count == 1){ 
     color(0,255, 0); // turn the RGB LED green 
     delay(1000); // delay for 1 second 
     count += 1; //increment the count 
    } 
    else if (count == 2){ 
     color(0, 0, 255); // turn the RGB LED blue 
     delay(1000); // delay for 1 second 
     count = 0; // set the count back to 0 
    } 
    } 

} 
void color (unsigned char red, unsigned char green, unsigned char blue)  // the color generating function 
{  
    analogWrite(redPin, 255-red); 
    analogWrite(bluePin, 255-blue); 
    analogWrite(greenPin, 255-green); 
}  

Answer 1

您沒有讀取切換銷的值，或者將該引腳設置爲輸入。

所以SwitchValue總是很低，你的條件總是爲真。所以它只是循環。