Arduino RGB LED随机PWM电平

Question

我正在尝试创建一个程序，它将随机选择给定阵列中的RGB LED的PWM值。它适用于第一种颜色蓝色。然后我以第二种颜色嵌套，绿色，我从显示中松开蓝色，只有绿色显示。

void loop() { 
    // put your main code here, to run repeatedly: 

    int x[9] = {0, 32, 64, 96, 128, 160, 192, 224, 256}; //setup Array X for brightness options 
    int blueVariable = 0;         //Blue LED 
    int greenVariable = 0;        //Green LED 
    for (int blueLed = 0; blueLed > -1;) {    //for loop to choose PWM option 
    analogWrite(11, x[blueVariable]);     //Initilize the PWM function on pin 11 to brightness of blueVariable 
    // if (blueLed == 255) blueLed = 0;     // 
    blueVariable = random(0,8);       //Random function to decide on blueVariable value 
    delay(500); 


    for (int greenLed = 0; greenLed > -1;) { 
     analogWrite(10, x[greenVariable]); 
     // if (g == 255) g = 0;    // switch direction at peak 
     greenVariable = random(0,255); 
    delay(500); 
    } 
    } 

} 

Answer 1

就有两个问题：

首先你迷上你的 “for循环” 在绿色的for循环蓝色（！）。基于循环运行无限的事实，你只能循环第二个for循环。

第二个问题（也许不是问题，但你看不到蓝色的原因）是你初始化blueVariable为0. 如果你第一次运行，你写入值0到PWM引脚。之后，您更改变量，但不要写入PWM引脚，因为您卡在“无限循环”中。

顺便说一句，就像在Michael的评论中说的那样，你应该把255改成8 AND，你应该把最后一个值（256）改成255，因为8bit PWM意味着0-255的256个值。

例子：

int x[9] = {0, 32, 64, 96, 128, 160, 192, 224, 255}; // Changed Value 

void loop() { 
    int blueVariable = 0;         //Blue LED 
    int greenVariable = 0;        //Green LED 

    while(1) {           // Because it was infinite already i changed it to while(1) 
    blueVariable = random(0,8);       //Put in front of analogWrite() 
    analogWrite(11, x[blueVariable]);     
    delay(500); 

    // Deleted the scond loop 
    greenVariable = random(0,8);      // Value changed from 255 to 8; Also put in front of analogWrite 
    analogWrite(10, x[greenVariable]); 
    delay(500); 
    }   
}