Turning on the LED after a while.

Hi Sofiia,

To do this properly is quite an advanced thing. There's a capability inside the Arduino (it is slightly different depending on which Arduino you are using, but at a high level, the concept is the same) called a timer. The timer can be programmed to generate something called an 'interrupt' which calls a special function (called an interrupt service routine) regularly, for example every second.

Then, you can use a global variable to count these 1-second ticks. Another global variable can be used to store state information related to (say) button press.

Button-presses need debouncing, that is another topic too,

To make a long story short, these two topics will require a lot of reading.

Some resources are here:

Timers and interrupts: https://learn.adafruit.com/multi-tasking-the-arduino-part-2/timers

Button debounce: https://blog.adafruit.com/2009/10/20/example-code-for-multi-button-checker-with-debouncing/

Hi Sofiia,

To do this properly is quite an advanced thing. There's a capability inside the Arduino (it is slightly different depending on which Arduino you are using, but at a high level, the concept is the same) called a timer. The timer can be programmed to generate something called an 'interrupt' which calls a special function (called an interrupt service routine) regularly, for example every second.

Then, you can use a global variable to count these 1-second ticks. Another global variable can be used to store state information related to (say) button press.

Button-presses need debouncing, that is another topic too,

To make a long story short, these two topics will require a lot of reading.

Some resources are here:

Timers and interrupts: https://learn.adafruit.com/multi-tasking-the-arduino-part-2/timers

Button debounce: https://blog.adafruit.com/2009/10/20/example-code-for-multi-button-checker-with-debouncing/

I made sketches, look, please. I need to add time, but I'm already confused with the millis () function. Correct, if there's a mistake.

class PauseFlasher
{
  const unsigned long maxValue = 4294967295UL; // maximum counter value

  int ledPin; 
  long OnTime; 
  long OffTime; 
  long PeriodFlashing; 
  long PeriodPause; 

  int ledState; 
  int ledFlashing; 
  int keyState, oldKeyState; 
  unsigned long previousMillis;
  unsigned long previousFlashingMillis; 
  unsigned long previousKeyMillis;

  public:
  PauseFlasher(int pin, long on, long off, long flashing, long pause)
  {
   ledPin = pin;
   pinMode(ledPin, OUTPUT);

   OnTime = on;
   OffTime = off;
   PeriodFlashing = flashing;
   PeriodPause = pause;

   ledState = HIGH;
   ledFlashing = HIGH;
   keyState = LOW;
   oldKeyState = HIGH;
   previousMillis = 0; 
   previousFlashingMillis = 0; 
   previousKeyMillis = 0;
  }

  void Update()
  {
    unsigned long currentMillis = millis(); 
    unsigned long temp_time=0, temp_time1=0;

    if (currentMillis >= previousFlashingMillis) temp_time1 = currentMillis - previousFlashingMillis;
    else temp_time1 = maxValue - previousFlashingMillis + currentMillis;

    if ((ledFlashing==HIGH) && (temp_time1 >= PeriodFlashing))
    {
      ledFlashing = LOW; 
      previousFlashingMillis = currentMillis; 
      digitalWrite(ledPin, ledFlashing); 
      keyState = LOW;
      oldKeyState= HIGH;
    }
    if ((ledFlashing==LOW) && (temp_time1 >= PeriodPause))
    {
      ledFlashing = HIGH; 
      previousFlashingMillis = currentMillis ; 
      digitalWrite(ledPin, ledFlashing); 
      keyState = LOW;
      oldKeyState= HIGH;
    }

    if(ledFlashing==HIGH)
    {
      if (currentMillis >= previousMillis) temp_time = currentMillis - previousMillis;
      else temp_time = maxValue  - previousMillis + currentMillis;
      
      if((ledState == HIGH) && (temp_time >= OnTime))
      {
        ledState = LOW; // выключаем
        previousMillis = currentMillis; 
        digitalWrite(ledPin, ledState); 
      }
      else if ((ledState == LOW) && (temp_time >= OffTime))
      {
        ledState = HIGH; // включаем
        previousMillis = currentMillis ; 
        digitalWrite(ledPin, ledState); 
      }
    }
    if(ledFlashing==LOW)
    {
      if (digitalRead(2)==HIGH)
      {
        if(millis()-previousKeyMillis>100)
        {
          previousKeyMillis = millis();
          if(keyState==oldKeyState)
          {
            if(keyState==LOW) keyState=HIGH;
            else if(keyState==HIGH) keyState=LOW;
            digitalWrite(ledPin, keyState);
          }  
        }
      }
      else oldKeyState=keyState;
    }
  }
};

PauseFlasher led1(13, 100, 200, 5000, 15000);

void setup(){}

void loop()
{
  led1.Update();
}

Hi Sofiia,

The code is hard to follow, possibly line 54 might need changing from "if" to "else if" but I'm only guessing, I could only partially understand the code.

You can use Serial.println to print out debug to try to get an idea where the code executes, and the values of variables to debug this, so that you can be sure that the values in the variables are what you expect.

Thanks. It remains to understand where to write what numbers (which I need), otherwise I’m already confused. Can you help me please?

Another couple of potentially useful resources:

Level Up Your Arduino Code: External Interrupts

https://www.youtube.com/watch?v=J61_PKyWjxU

Level Up Your Arduino Code: Timer Interrupts

https://www.youtube.com/watch?v=2kr5A350H7E

This one is not Arduino IDE but still a good introduction to the AVR peripherals such as GPIO and timer/counters:

Getting Started With AVR

https://www.youtube.com/playlist?list=PLtQdQmNK_0DRhBWYZ32BEILOykXLpJ8tP

There's no guideline on where to write the values, it just needs to be done wherever you suspect (after running the code and seeing the result for example) there could be an error, or wherever you want to be sure the value is changing as expected.

You can comment them out afterwards if you don't need them after debugging.