uint8_t pcf8583_active_alarm = 0;

void EXTI15_10_IRQHandler(void)
{
  // Here would be the B1 pin interrupt handler (do where it says "do something..."):
  if ((EXTI_GetITStatus(EXTI_Line13)) != RESET) {
    // do something...
    if (pcf8583_active_alarm) {
      pcf8583_stop_alarm();
      pcf8583_active_alarm = 0;
    }
    EXTI_ClearITPendingBit(EXTI_Line13);
  }
}

uint8_t s[4]; // buffer used for conversions

int main(void)
{
  /* local variables */
  uint8_t current_sec = 0, old_sec = 0;
  /* mandatory system initializations */
  vpc_system_init();
  //vpc_rtc_init(); /* enable if required */
  vpc_gpio_init();
  //vpc_usart2_uart_init(); /* enable if required */
  vpc_i2c1_init();
  /* third-party initializations */
  lcd_init(LCD_HD44780);

	RTC_seconds = 55; // 0 to 59
	RTC_minutes = 59; // 0 to 59
	RTC_hours = 23; // 0 to 23
	RTC_day = 13; // 1 to 31
	RTC_month = 5; // 1 to 12
	RTC_century = 20; //
	RTC_year = 14; // 0 to 99
	RTC_dayofweek = 0; // 0 to 6 (Sun=0, Mon=1, etc..)
	RTC_leapyear = 2; // 0 to 3 (0 - is leapyear and 1,2,3 not)
	// 2012 was leapyear    ( leapyear = 0)
	// 2014 is not leapyear ( leapyear = 2)
	//
	pcf8583_set_datetime(RTC_hours, RTC_minutes, RTC_seconds, RTC_dayofweek,
			RTC_day, RTC_month, RTC_leapyear, RTC_century, RTC_year);
	// =====================================================================

	// =================== SET THE ALARM ===================================
	pcf8583_en_dis_alarm(PCF8583_WEEKDAYS_ALARM);
	pcf8583_set_alarm_time(0, 0, 0);
	//In which days alarm is on: SU   MO   TU   WE   TH   FR     SA
	pcf8583_set_alarm_weekdays(RESET, SET, SET, SET, SET, SET, RESET);
	// =====================================================================

  while(1) {
    /* your forever repeating code */
    pcf8583_get_datetime(&RTC_hours, &RTC_minutes, &RTC_seconds,
                         &RTC_dayofweek, &RTC_day, &RTC_month, &RTC_leapyear,
                         &RTC_century, &RTC_year);
    current_sec = RTC_seconds;
    if (current_sec != old_sec) {
      old_sec = current_sec;
      // show time
      lcd_cursor_position(0, 0);
      byte2dec(RTC_hours, s);
      if (s[1] == ' ')
        _lcd_write_data('0');
      else
        _lcd_write_data(s[1]);
      _lcd_write_data(s[2]);
      _lcd_write_data(':');
      byte2dec(RTC_minutes, s);
      if (s[1] == ' ')
        _lcd_write_data('0');
      else
        _lcd_write_data(s[1]);
      _lcd_write_data(s[2]);
      _lcd_write_data(':');
      byte2dec(RTC_seconds, s);
      if (s[1] == ' ')
        _lcd_write_data('0');
      else
        _lcd_write_data(s[1]);
      _lcd_write_data(s[2]);
      // show date on the second line
      lcd_cursor_position(1, 0);
      byte2dec(RTC_day, s);
      if (s[1] == ' ')
        _lcd_write_data('0');
      else
        _lcd_write_data(s[1]);
      _lcd_write_data(s[2]);
      _lcd_write_data('/');
      byte2dec(RTC_month, s);
      if (s[1] == ' ')
        _lcd_write_data('0');
      else
        _lcd_write_data(s[1]);
      _lcd_write_data(s[2]);
      _lcd_write_data('/');
      byte2dec(RTC_century, s);
      _lcd_write_data(s[1]);
      _lcd_write_data(s[2]);
      byte2dec(RTC_year, s);
      _lcd_write_data(s[1]);
      _lcd_write_data(s[2]);
      lcd_cursor_position(0, 13);
      switch(RTC_dayofweek){
        case 0: 
          lcd_write_str((uint8_t *)"SUN");
          break;
        case 1: 
          lcd_write_str((uint8_t *)"MON");
          break;
        case 2: 
          lcd_write_str((uint8_t *)"TUE");
          break;
        case 3: 
          lcd_write_str((uint8_t *)"WED");
          break;
        case 4: 
          lcd_write_str((uint8_t *)"THU");
          break;
        case 5: 
          lcd_write_str((uint8_t *)"FRI");
          break;
        case 6: 
          lcd_write_str((uint8_t *)"SAT");
          break;
      }
      if (pcf8583_active_alarm)
        GPIO_SetBits(LD2_GPIO_Port, LD2_Pin); // alarm - LED continuously lit
      else
        GPIO_ToggleBits(LD2_GPIO_Port, LD2_Pin); // blink
    }
    if (!GPIO_ReadInputDataBit(ALARM_GPIO_Port, ALARM_Pin))
      pcf8583_active_alarm = 1;
  }
  return 0;
}