在一定时间内未触摸调光按钮后，LED处于全亮度

Question

我做了一个简单的单按钮LED调光器，我希望在按钮未被触摸一段时间后，LED恢复到全亮度。但我想出的代码似乎不起作用，因为我无法调暗LED

int buttonPin = 12;
int LEDPin = 3;
int buttonVal;
int LEDbright = 0;
int dt = 500;
int fdt = 60000;
void setup() {
// put your setup code here, to run once:
pinMode(buttonPin, INPUT);
pinMode(LEDPin, OUTPUT);
Serial.begin(9600);
}
void loop() {
static unsigned long whenButtonWasTouchedMs = 0;
buttonVal = digitalRead(buttonPin);
Serial.print("Button = ");
Serial.print(buttonVal);
Serial.print(", ");
delay(dt);
if (buttonVal == 1) {
LEDbright = LEDbright + 20;
whenButtonWasTouchedMs = millis();

}
Serial.println(LEDbright);
//
if (LEDbright > 255) {
LEDbright = 255;
delay(dt);
}
unsigned long afterButtonWasTouchedMs = millis() - whenButtonWasTouchedMs;
if (afterButtonWasTouchedMs >= 60000) {
LEDbright = 0;
analogWrite(LEDPin, LEDbright);
}
}

Answer 1

您的问题似乎与代码的编写方式不一致。看起来你想做相反的事情(按下按钮时让灯变亮，然后在按钮释放60秒后关闭(。以下是我为解决您提出的问题而提出的代码：

int buttonPin = 12;
int LEDPin = 3;
int buttonVal;
int whenButtonWasTouched;
unsigned int LEDbright = 255;
int dt = 500;
int fdt = 60000;
unsigned long whenButtonWasTouchedMs = 0;
void setup() {
// put your setup code here, to run once:
pinMode(buttonPin, INPUT);
pinMode(LEDPin, OUTPUT);
Serial.begin(9600);
}
void loop() {
//static unsigned long whenButtonWasTouchedMs = 0;
buttonVal = digitalRead(buttonPin);
Serial.print("Button = ");
Serial.print(buttonVal);
Serial.print(", ");
delay(dt);
if (buttonVal == 1) {
LEDbright = LEDbright - 20;
whenButtonWasTouchedMs = millis();

}
//
if (LEDbright < 20 || LEDbright > 255) { // The LEDbright > 255 part is because sometimes there can be an integer overflow if we don't keep this.
LEDbright = 0;
}  
Serial.println(LEDbright);
unsigned long afterButtonWasTouchedMs = millis() - whenButtonWasTouched;
if (afterButtonWasTouchedMs >= 60000) {
LEDbright = 255;
}    
analogWrite(LEDPin, LEDbright);
}

正如你所看到的，我更改了它，使analogWrite不在if语句中，它检查整数溢出，并打印出led亮度的调整值。要使其在按住按钮时变得更亮，然后在60秒后关闭，只需将LEDbright调整行中的减号改为加号，并更改周围的一些其他值。

Answer 2

int buttonPin = 12;
int LEDPin = 3;
int buttonVal;
unsigned int LEDbright = 0;
int dt = 500;
int fdt = 60000;
unsigned long whenButtonWasTouchedMs = 0;
void setup() {
// put your setup code here, to run once:
pinMode(buttonPin, INPUT);
pinMode(LEDPin, OUTPUT);
Serial.begin(9600);
}
void loop() {
//static unsigned long whenButtonWasTouchedMs = 0;
buttonVal = digitalRead(buttonPin);
Serial.print("Button = ");
Serial.print(buttonVal);
Serial.print(", ");
delay(dt);
if (buttonVal == 1) {
LEDbright = LEDbright + 20;
whenButtonWasTouchedMs = millis();

}
if (LEDbright > 255) {
LEDbright = 255;
delay(dt);
} 
Serial.println(LEDbright);
unsigned long afterButtonWasTouchedMs = millis() - whenButtonWasTouchedMs;
if (afterButtonWasTouchedMs >= 60000) {
LEDbright = 0;
}    
analogWrite(LEDPin, LEDbright);
}