Question

我有一个代码，一旦它通过串行接收特定输入，它将2个引脚变为高电平，并等待中断发生并运行其代码。我尝试使用无限loop(while 1)但按下按钮时无法执行中断例程。

我希望输出LED和BEEP在收到'C'之后切换，直到中断发生。

// Declarations before

void loop() {
    while(Serial.available())
    { 
        char data = Serial.read();  
        if(data == 'C')
        {
            digitalWrite(BEEP, 1);
            digitalWrite(LED, 1);
            flag = true;
        }   
    }

// Interrupt routine

Answer 1

我刚在模拟器上试过这个：

#define ITR_PIN 3

volatile boolean start = false;

volatile boolean flag = false;

int LED= 4;

/**
 * This method is called on the interruption raised on the falling front of the PIN2
 * The start flag is used to avoid rebound front. Interruptions are disabled inside the 
 * interrupt vector method.
 * start is reset once it has been processed in the main loop() 
 */
void buttonPressed()
{
  if(flag)
  {
    if (!start)
    {
      start = true;
    }
  }
}

void setup()
{
  cli();
  pinMode(ITR_PIN, INPUT);
  pinMode(LED, OUTPUT);
  attachInterrupt(0, buttonPressed, FALLING); // Pin 3
  sei();
  Serial.begin(9600);  
}

void loop(){

  while(Serial.available())
  { 
    char data = Serial.read();   

    if(data == 'C')
    {
      digitalWrite(LED, 1);
      flag = true;
    } 
  }

  if(flag == true)
    if (start)
    {
      digitalWrite(LED, LOW);
      delay(50);
      start = false;
      flag=false;  
    }
}

（它只是你的缩小版本，我刚刚删除了步进器依赖项并将标记标记为易失性）。它适用于这个硬件：

arduino micro sample circuit

但是，我很确定你没有在你的赛道上添加上拉！

解决方案是：

在引脚3和+ 5V
启用内部上拉

解决方案2是首选方案：您只需要更改

pinMode(ITR_PIN, INPUT);

到

pinMode(ITR_PIN, INPUT_PULLUP);

修改

根据你的评论，我认为行为应该是不同的：

一切都已关闭

当您在串行接口上收到C时，指示灯开始“闪烁”

当断言中断时，它会停止闪烁。

我修改了代码来实现这个目标;我稍微减少了其余的代码（但你可以将它与前一个代码合并）

#define ITR_PIN 3 volatile boolean flag = false; const int blink_period_ms = 500; // Blink period in milliseconds unsigned long initialBlinkTime; int LED= 4; void buttonPressed() { flag = false; } void setup() { cli(); pinMode(ITR_PIN, INPUT); pinMode(LED, OUTPUT); attachInterrupt(0, buttonPressed, FALLING); // Pin 3 sei(); Serial.begin(9600); } void loop(){ while(Serial.available()) { char data = Serial.read(); if(data == 'C') { if (!flag) { initialBlinkTime = millis(); flag = true; } } } if(flag) { int currentTime = millis() - initialBlinkTime; while (currentTime > blink_period_ms) currentTime -= blink_period_ms; digitalWrite(LED, currentTime < blink_period_ms/2); // Insert here the other instructions delay(50); } }

Answer 2

当此代码从串行接收到'C'字符时，代码开始闪烁50毫秒并且50毫秒关闭，当产生中断ITR_PIN时，LED闪烁停止（将调用ISR buttonPressed函数！）

#define ITR_PIN 3

volatile bool start = false;
bool ledstatus = false;

int LED= 4;

/**
 * This method is called on the interruption raised on the falling front of the PIN2
 * The start flag is used to avoid rebound front. Interruptions are disabled inside the
 * interrupt vector method.
 * start is reset once it has been processed in the main loop()
 */
void buttonPressed()
{
    start=false;
}

void setup()
{
    cli();
    pinMode(ITR_PIN, INPUT);
    pinMode(LED, OUTPUT);
    attachInterrupt(0, buttonPressed, FALLING); // Pin 3
    sei();
    Serial.begin(9600);
}

void loop(){

    while(Serial.available())
    {
        char data = Serial.read();

        if(data == 'C')
        {
          start = true;
        }
    }

    if (start)
    {
        ledstatus=!ledstatus;
        digitalWrite(LED, (ledstatus)?HIGH:LOW);
        delay(50);
    } else {
        if (ledstatus) {
            ledstatus=false;
            digitalWrite(LED,LOW);
        }
    }        

}

在不中断操作的情况下切换Arduino Micro上的引脚

2 个答案: