MSP430F5418的RTC设置问题

参考以下例程试试先

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//******************************************************************************
// MSP430F54xA Demo - RTC_A in real time clock mode
//
// Description: This program demonstrates the RTC mode by triggering an
// interrupt every second and minute. This code toggles P1.0 every second.
// This code recommends an external LFXT1 crystal for RTC accuracy.
// ACLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO = 32 x ACLK = 1048576Hz
//
// MSP430F54xA
// -----------------
// /|\ | XIN|-
// | | | 32kHz
// ---|RST XOUT|-
// | |
// | P1.0 |--> Toggles every second
// | |
//
// W. Goh
// Texas Instruments Inc.
// April 2010
// Built with CCS version 4.2 and IAR Embedded Workbench Version: 4.21.8
//******************************************************************************

#include <msp430.h>

int main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop Watchdog Timer
P1DIR |= BIT0; // Set P1.0 as output

// Initialize LFXT1
P7SEL |= 0x03; // Select XT1
UCSCTL6 &= ~(XT1OFF); // XT1 On
UCSCTL6 |= XCAP_3; // Internal load cap

// Loop until XT1,XT2 & DCO fault flag is cleared
do
{
UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + XT1HFOFFG + DCOFFG);
// Clear XT2,XT1,DCO fault flags
SFRIFG1 &= ~OFIFG; // Clear fault flags
}while (SFRIFG1&OFIFG); // Test oscillator fault flag

// Configure RTC_A
RTCCTL01 |= RTCTEVIE + RTCRDYIE + RTCBCD + RTCHOLD + RTCMODE;
// RTC enable, BCD mode, RTC hold
// enable RTC read ready interrupt
// enable RTC time event interrupt

RTCYEAR = 0x2010; // Year = 0x2010
RTCMON = 0x4; // Month = 0x04 = April
RTCDAY = 0x05; // Day = 0x05 = 5th
RTCDOW = 0x01; // Day of week = 0x01 = Monday
RTCHOUR = 0x10; // Hour = 0x10
RTCMIN = 0x32; // Minute = 0x32
RTCSEC = 0x45; // Seconds = 0x45

RTCADOWDAY = 0x2; // RTC Day of week alarm = 0x2
RTCADAY = 0x20; // RTC Day Alarm = 0x20
RTCAHOUR = 0x10; // RTC Hour Alarm
RTCAMIN = 0x23; // RTC Minute Alarm

RTCCTL01 &= ~(RTCHOLD); // Start RTC calendar mode

__bis_SR_register(LPM3_bits + GIE); // Enter LPM3 mode with interrupts
// enabled
__no_operation();
}

#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=RTC_VECTOR
__interrupt void RTC_ISR(void)
#elif defined(__GNUC__)
void __attribute__ ((interrupt(RTC_VECTOR))) RTC_ISR (void)
#else
#error Compiler not supported!
#endif
{
switch(__even_in_range(RTCIV,16))
{
case RTC_NONE: // No interrupts
break;
case RTC_RTCRDYIFG: // RTCRDYIFG
P1OUT ^= 0x01; // Toggles P1.0 every second
break;
case RTC_RTCTEVIFG: // RTCEVIFG
__no_operation(); // Interrupts every minute
break;
case RTC_RTCAIFG: // RTCAIFG
break;
case RTC_RT0PSIFG: // RT0PSIFG
break;
case RTC_RT1PSIFG: // RT1PSIFG
break;
case 12: break; // Reserved
case 14: break; // Reserved
case 16: break; // Reserved
default: break;
}
}

中断处理函数用来做什么的？还有就是，经常存不进去，写改变不了。

你都已经用Struct，贴一下g_now的结构呢？

driverlib 里有个和你这个类似的Calendar 结构，建议你用driverlib。

结构体是这样定义的：

typedef struct
{
unsigned int Year;
unsigned char Month;
unsigned char Day;
unsigned char Hour;
unsigned char Min;
unsigned char Sec;
}DateTime;