Reddit 12-hour blinker timer v 1.0

/*
  October 25, 2018
  This is a 12-hour repeating timer sketch for Arduino. It begins counting 12 hours from whenever it is powered on, or the [reset] button is pressed.
  When the time limit has been reached, the timer resets and calls the function time_event_function()
  (the last function in the code below)
  It also blinks the pin-13 LED on every 5 seconds, for one second.

  This code doesn't really do anything other than slowly blink the pin-13 LED, since there is not anything in the time_event_function().
*/

unsigned long oneSecond_beginTime = 0;
unsigned long oneSecond_currentTime = 0;

int seconds_counter = 0;
int minutes_counter = 0;
int hours_counter = 0;
int target_hours = 12; // This is the value in hours that you wanted the timer to wait for.

int ledCycle = 5; // This value means that the pin-13 LED will blink on every 5 seconds, and stay on for one second.
// If you have a device that is set to wait very long times between acting,
// it is wise to have it blink an indicator LED regularly so that you can tell that it is still working.


void setup() {

  pinMode(13, OUTPUT); // The pin# 13 LED will be used as our blinker indicator.

}


void loop() {
  check_for_one_second();
  check_seconds();
  check_minutes();
  check_hours_target();
}

void check_for_one_second() {
  // The code below is only for timing one second.
  oneSecond_currentTime = millis();
  if (oneSecond_currentTime >= oneSecond_beginTime) {
    if (oneSecond_currentTime >= (oneSecond_beginTime + 1000)) { // ------> if 1 second has passed since the time was set in oneSecond_beginTime
      seconds_counter += 1; // -------------------------------------------> then add 1 to the value seconds_counter here.
      oneSecond_beginTime = millis(); // ---------------------------------> and then reset the oneSecond_beginTime to the current time.
      cycle_blinkerLED();
    }
  }
  else {
    // This line is to reset the beginTime if the millis() value has rolled over.
    oneSecond_beginTime = millis();
  }
}

void cycle_blinkerLED() {
  // Below is what blinks the pin-13 LED on and off:
  int x = seconds_counter % ledCycle;
  if (x == 0) {
    // ledCycle is set to 5.
    // So every time that the seconds_counter value is evenly divisible by the ledCycle value,
    // The ledBlinkPin will get turned on.
    digitalWrite(13, 1);
  }
  else {
    // Every time that the seconds_counter value is NOT evenly divisible by the ledCycle value, the ledBlinkPin will get turned off.
    // And this check gets run every second, so the LED will only stay on for 1 second at a time.
    // This part means it will get turned 'off' 80% of all the 1-second intervals,
    // but repeatedly turning it 'on' or 'off' when it is already set {that way} doesn't harm it.
    digitalWrite(13, 0);
  }
}

void check_seconds() {
  if (seconds_counter >= 60) {
    seconds_counter = 0;
    minutes_counter += 1;
  }
}

void check_minutes() {
  if (minutes_counter >= 60) {
    minutes_counter = 0;
    hours_counter += 1;
  }
}

void check_hours_target() {
  if (hours_counter >= target_hours) {
    hours_counter = 0;
    target_reached();
  }
}

void target_reached() {
  time_event_function();
  reset_timer();
}

void reset_timer() {
  seconds_counter = 0;
  minutes_counter = 0;
  hours_counter = 0;
}

void time_event_function() {
  // This is the place where you put your own commands, for whatever you want to happen every 12 hours.

}


// [the end]