如何使用arduino中的PWM在5s内淡出led

Posted 2021-05-01

如何使用arduino中的PWM在5s内制作LED淡出。我写了这个函数，它没用。我试着调用这个函数。

const int minPWM = 0;
const int maxPWM = 255;
int fadeValue = 255;
int fadeIncrement = 5;
unsigned long previousFadeMillis;
int fadeInterval = 50;

void setLightPWM(unsigned long thisMillis) {

  if (thisMillis - previousFadeMillis >= fadeInterval) {

 fadeValue = fadeValue - fadeIncrement;
 if (fadeValue <= minPWM) {
   // At min, limit and change direction
   fadeValue = minPWM;
 }


   analogWrite(garageLED, fadeValue);


  previousFadeMillis = thisMillis;
}
   return;
}

另外，我在循环（）中写了这一行

  unsigned long currentMillis = millis();

  setLightPWM(currentMillis);