MSP432P401R: RTC calibration doesn't work as expected

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/*******************************************************************************
 * MSP432 RTC_C - Calendar Mode
 *
 * Description: This program demonstrates the RTC mode by triggering an
 * interrupt every minute. The date is set at the start of execution and an
 * additional alarm for a specific time is also set to demonstrate the various
 * modes of alarms/events for the RTC_C module.
 *
 *                MSP432P401
 *             ------------------
 *         /|\|                  |
 *          | |                  |
 *          --|RST         P1.0  |---> P1.0 LED
 *            |     PJ.0 LFXIN   |---------
 *            |                  |         |
 *            |                  |     < 32khz xTal >
 *            |                  |         |
 *            |     PJ.1 LFXOUT  |---------
 *            |                  |
 *            |                  |
 *            |     P4.3 RTCCLK  |-------->
 *
 ******************************************************************************/
/* DriverLib Includes */
#include <ti/devices/msp432p4xx/driverlib/driverlib.h>
#include <ti/devices/msp432p4xx/inc/msp.h>

/* Statics */
 static volatile RTC_C_Calendar newTime;

 //![Simple RTC Config]
 /* Time is Saturday, November 12th 1955 10:03:00 PM */
 const RTC_C_Calendar currentTime =
 {
         0x00,
         0x03,
         0x22,
         0x06,
         0x12,
         0x11,
         0x1955
 };
 //![Simple RTC Config]

int main(void)
{
    /* Halting WDT  */
    MAP_WDT_A_holdTimer();

    /* Configuring pins for peripheral/crystal usage and LED for output */
    MAP_GPIO_setAsPeripheralModuleFunctionOutputPin(GPIO_PORT_PJ,
            GPIO_PIN0 | GPIO_PIN1, GPIO_PRIMARY_MODULE_FUNCTION);

    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_P1, GPIO_PIN0);
    MAP_GPIO_setAsOutputPin(GPIO_PORT_P1, GPIO_PIN0);

    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_P2, GPIO_PIN0);
    MAP_GPIO_setAsOutputPin(GPIO_PORT_P2, GPIO_PIN0);

    /*
     * RTC Calibration output
     */
    MAP_GPIO_setAsPeripheralModuleFunctionOutputPin(GPIO_PORT_P4,
            GPIO_PIN3, GPIO_SECONDARY_MODULE_FUNCTION);

    /* Setting the external clock frequency. This API is optional, but will
     * come in handy if the user ever wants to use the getMCLK/getACLK/etc
     * functions
     */
    MAP_CS_setExternalClockSourceFrequency(32000,48000000);

    /* Starting LFXT in non-bypass mode without a timeout. */
    MAP_CS_startLFXT(CS_LFXT_DRIVE3);

    //![Simple RTC Example]
    /* Initializing RTC with current time as described in time in
     * definitions section */
    MAP_RTC_C_initCalendar(&currentTime, RTC_C_FORMAT_BCD);

    /* Specify an interrupt to assert every minute */
    MAP_RTC_C_setCalendarEvent(RTC_C_CALENDAREVENT_MINUTECHANGE);

//    RTC_C->PS0CTL = RTC_C_PS0CTL_RT0IP_7;
    RTC_C->PS1CTL = RTC_C_PS1CTL_RT1IP_3;

    /* Enable interrupt for RTC Ready Status, which asserts when the RTC
     * Calendar registers are ready to read.
     * Also, enable interrupts for the Calendar alarm and Calendar event. */
    MAP_RTC_C_clearInterruptFlag(
            RTC_C_CLOCK_READ_READY_INTERRUPT | RTC_C_TIME_EVENT_INTERRUPT
                    | RTC_C_PRESCALE_TIMER0_INTERRUPT | RTC_C_PRESCALE_TIMER1_INTERRUPT);
    MAP_RTC_C_enableInterrupt(RTC_C_TIME_EVENT_INTERRUPT|RTC_C_PRESCALE_TIMER1_INTERRUPT);

    MAP_RTC_C_setCalibrationFrequency(RTC_C_CALIBRATIONFREQ_512HZ);

    /*
     * Apply calibration before starting clock
     * +1 ppm
     */
//    MAP_RTC_C_setCalibrationData(RTC_C_CALIBRATION_UP1PPM,1);
    MAP_RTC_C_setCalibrationData(RTC_C_CALIBRATION_DOWN1PPM,2);

    /* Start RTC Clock */
    MAP_RTC_C_startClock();
    //![Simple RTC Example]

    /* Enable interrupts and go to sleep. */
    MAP_Interrupt_enableInterrupt(INT_RTC_C);
    MAP_Interrupt_enableSleepOnIsrExit();
    MAP_Interrupt_enableMaster();

    while(1)
    {
        MAP_PCM_gotoLPM0();
    }

}

/* RTC ISR */
void RTC_C_IRQHandler(void)
{
    uint32_t status;

    status = MAP_RTC_C_getEnabledInterruptStatus();
    MAP_RTC_C_clearInterruptFlag(status);

    if (status & RTC_C_PRESCALE_TIMER1_INTERRUPT)
    {
        MAP_GPIO_toggleOutputOnPin(GPIO_PORT_P2, GPIO_PIN0);
    }

    if (status & RTC_C_TIME_EVENT_INTERRUPT)
    {
        /* Interrupts every minute - Set breakpoint here */
        MAP_GPIO_toggleOutputOnPin(GPIO_PORT_P1, GPIO_PIN0);
        __no_operation();
    }

}