MSP-EXP430FR5994: RTC Configuration (to avoid setting the RTC time upon each MCU reset)

Hi,

  I have gone through the RTC configuration example section as part of the Out-of-box demo for MSP-EXP430FR5994. In the code below, it shows how to set the RTC upon system startup. But how do I skip the RTC setting upon system startup? I mean that the RTC is holding its value (rather maintaining the clock) and upon system startup I do not want to set the time again, I just want the RTC to continue and I will fetch the time whenever necessary. I commented the blue coloured section below to see if it helps; but this results into wrong RTC time (during RTC value read). For example, the original year setting was 'Year = 0x2018' but while reading the year value after an MCU reset, the value came as 843 (decimal).

  Note that in my application, I kept the RTC running in BCD mode while the application uses binary mode for its internal calculations. For setting the clock & for retrieving the same, the driverlib BCDtoBinary & BinaryToBCD functions have been used.

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void Init_RTC()
{
    //Setup Current Time for Calendar
    calendar.Seconds    = 0x00;
    calendar.Minutes    = 0x00;
    calendar.Hours      = 0x00;
    calendar.DayOfWeek  = 0x01;
    calendar.DayOfMonth = 0x01;
    calendar.Month      = 0x01;
    calendar.Year       = 0x2019;

    // Initialize RTC with the specified Calendar above
    RTC_C_initCalendar(RTC_C_BASE,
                       &calendar,
                       RTC_C_FORMAT_BCD);

    RTC_C_setCalendarEvent(RTC_C_BASE,
                           RTC_C_CALENDAREVENT_MINUTECHANGE
                           );

    RTC_C_clearInterrupt(RTC_C_BASE,
                         RTC_C_TIME_EVENT_INTERRUPT
                         );

    RTC_C_enableInterrupt(RTC_C_BASE,
                          RTC_C_TIME_EVENT_INTERRUPT
                          );

    //Start RTC Clock
    RTC_C_startClock(RTC_C_BASE);
}

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Thanks

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Regards

Soumyajit