如何在蓝牙命令后使 LED 亮 5 秒

Question

我想通过 galileo gen 2 上的蓝牙模块 (hc 05) 控制一个 LED。我需要以下程序：发送一个字符后，比如说“1”，连接到引脚 2 的 LED 亮 5 秒，然后然后它关闭并等待另一个命令。我怎么能这样做？

我试过代码： （这实际上适用于 Galileo Gen 2，但我的蓝牙工作正常，我在其他示例中检查了打开和关闭 LED）

include TimerOne.h

TTYUARTClass* gSerialOnePtr = &Serial1;
char input;
int led = 2;
long offAt = 0;

enum States  // set values for enum Mode
{   
    on,
    off
};

States currentState, nextState;

void setup()
{
  Timer1.initialize(1000000); // seting interrupt time to 1 sec
  Timer1.attachInterrupt(checkBluetooth); // Declaring ISR Function name
  gSerialOnePtr->begin(9600);        //start serial connection
 pinMode(led, OUTPUT); 
  currentState = off;
}

void loop()
{
  switch(currentState)    // android app sends letters from A to I each letter turn on different Mode.
   { 
     case on://red color
       ledOn();
       break;

     case off://green color
       ledOff();
       break;       

     default: 
       ledOff();
       break;
   }
  currentState = nextState;  //saving next mode in current mode.
}

 void checkBluetooth()        //ISR for timer1
{

    if(gSerialOnePtr->available())  // checking if data arrived from bluetooth module.
    {
      input = gSerialOnePtr->read();  // save character from serial in bt.

      if(input == '1')         
      {
        currentState = on;
      }
      else if(input == '2')         
      {  
        currentState = off;
      }
    }
}

void ledOn()
{
  if( (digitalRead(led) == LOW ) ) 
  { 
    digitalWrite(led, HIGH);
    offAt = millis() + 5000; //store var of now + 5 seconds
  }

  if(digitalRead(led) == HIGH) //if led is on
  {
      if(millis() >= offAt) //see if it's time to turn off LED
      {
         digitalWrite(led, LOW); //it's time. this also re-enables the button
      }
  }
}
void ledOff()
{
  digitalWrite(led, LOW);
}

它还没有工作......

Answer 1

我认为你的问题是线

currentState = nextState;  //saving next mode in current mode.

尝试评论它。或者，如果你想以我认为你想要的方式使用它，你必须写

void setup()
{
  [...]
  currentState = off;
  nextState = off;
}

[...]

void checkBluetooth()        //ISR for timer1
{
    if(gSerialOnePtr->available())
    {
      input = gSerialOnePtr->read();  // save character from serial in bt.

      if(input == '1')         
      {
        nextState = on;
      }
      else if(input == '2')         
      {  
        nextState = off;
      }
    }
}

顺便说一句，我也会写

while(gSerialOnePtr->available())

因此，如果您向其发送一个 10 字节的数组，则不必等待 10 秒...我个人也会将中断时间减少到 0.1 秒，但这不是强制性的..

编辑：

要在 5 秒后关闭，我会写

NON RETRIGGERABLE METHOD（即，如果您在开启时发送“1”，它将被丢弃）

unsigned long startTime;

void setup()
{
  [...]
  startTime = 0;
}

[...]

void ledOn()
{
    digitalWrite(led, HIGH);

    if (millis() - startTime > 5000)
        nextState = off;
}

void ledOff()
{
    digitalWrite(led, LOW);
    startTime = millis();
}

RETRIGGERABLE METHOD（即，如果您在 5 秒后发送“1”将重新开始）

unsigned long startTime;

void setup()
{
  [...]
  startTime = 0;
}

[...]

void checkBluetooth()
{
    [...]
        if(input == '1')         
        {
            nextState = on;
            startTime = millis();
        }
        else if(input == '2')         
        { 
    [...]
}    

void ledOn()
{
    digitalWrite(led, HIGH);

    if (millis() - startTime > 5000)
        nextState = off;
}

void ledOff()
{
    digitalWrite(led, LOW);
}