MSP432 Stop RTC

#include "msp.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>

void set_rtc(char *date){
	RTCCTL0_H = RTCKEY_H;                       //   Unlock RTC key protected registers
	RTCYEAR = strtol(&date[ 0], NULL, 16);
	RTCMON  = strtol(&date[ 5], NULL, 16);
	RTCDAY  = strtol(&date[ 8], NULL, 16);
	RTCHOUR = strtol(&date[11], NULL, 16);
	RTCMIN  = strtol(&date[14], NULL, 16);
	RTCSEC  = strtol(&date[17], NULL, 16);
    RTCCTL0_H = 0;                              //   Lock RTC key protected registers
}

void main(void)
{
    WDTCTL = WDTPW | WDTHOLD;           // Stop watchdog timer
    P1DIR |= BIT0;                      // Configure P1.0 as output (rosso)
    P1OUT &= ~BIT0;

	// ==========Configurazione Real Time Clock==========
    RTCCTL0_H = RTCKEY_H;                    // Unlock RTC key protected registers
    RTCPS1CTL |= RT1PSIE;					 // Interrupt disable
    RTCPS1CTL |= RT1IP_4;					 // 0.5 seconds
    RTCPS1CTL &= ~(RT1PSIFG);
    RTCCTL1 = RTCBCD | RTCHOLD;              // BCD select (calendar register), RTCHOLD counters and prescale counters actived
    // RTC enable, BCD mode, RTC hold
    // enable RTC read ready interrupt
    // enable RTC time event interrupt
    RTCCTL1 &= ~(RTCHOLD);                    // Start RTC calendar mode
    RTCCTL0_H = 0;                            // Lock the RTC registers

    NVIC_ISER0 = 1 << ((INT_RTC_C - 16) & 31);

    SCB_SCR |= SCB_SCR_SLEEPONEXIT;    // Enable sleep on exit from ISR
    __enable_interrupt();

	set_rtc("2000-01-01 00:00:00");		// Set rtc
}

// RTC interrupt service routine
void RtcIsrHandler(void)
{
    if (RTCPS1CTL & RT1PSIFG)
    {
    	P1OUT ^= BIT0; //
    }
    RTCCTL0_H = RTCKEY_H ;
	RTCPS1CTL &= ~RT1PSIFG;
	RTCCTL0_H = 0;
}