MSP430FR6972: 运行一两个月后看门狗无法复位芯片

void main(void)
{
  uint16_t i;
  WDT_A_hold(WDT_A_BASE);
  GpioConfig();
  Kp2InterruptConfig();
  CsConfig();
  RtcConfig();
  __enable_interrupt();
  while (power_state == 0)
  {
    LED_RED_OFF;
    __bis_SR_register(LPM3_bits);
    __no_operation(); // BREAKPOINT HERE to verify the
    while (IS_KP2_LOW)
    {
      LED_RED_ON;
      if (rtc_sec - kp2_time > 1)
      {
        power_state = 1;
        break;
      }
    }
  }
  LED_GREEN_ON;
  LED_RED_ON;
  LED_YELLOW_ON;
  
  while(1)
  {
  }
}
void Kp2InterruptConfig(void)
{
  GPIO_selectInterruptEdge(
      KP2_PORT,
      KP2_PIN,
      GPIO_HIGH_TO_LOW_TRANSITION);
  GPIO_clearInterrupt(
      KP2_PORT,
      KP2_PIN);
  GPIO_enableInterrupt(
      KP2_PORT,
      KP2_PIN);
}

void CsConfig(void)
{
    GPIO_setAsPeripheralModuleFunctionInputPin(
        GPIO_PORT_PJ,
        GPIO_PIN4 + GPIO_PIN5,
        GPIO_PRIMARY_MODULE_FUNCTION
    );

    //Set DCO frequency to 8 MHz
    CS_setDCOFreq(CS_DCORSEL_0,CS_DCOFSEL_6);
    //Set external clock frequency to 32.768 KHz
    CS_setExternalClockSource(32768,0);
    //Set ACLK=LFXT
    CS_initClockSignal(CS_ACLK,CS_LFXTCLK_SELECT,CS_CLOCK_DIVIDER_1);
    //Set SMCLK = DCO with frequency divider of 1
    CS_initClockSignal(CS_SMCLK,CS_DCOCLK_SELECT,CS_CLOCK_DIVIDER_1);
    //Set MCLK = DCO with frequency divider of 1
    CS_initClockSignal(CS_MCLK,CS_DCOCLK_SELECT,CS_CLOCK_DIVIDER_1);
    //Start XT1 with no time out
    CS_turnOnLFXT(CS_LFXT_DRIVE_0);
}

void RtcConfig(void)
{
    GPIO_setAsPeripheralModuleFunctionInputPin(
        GPIO_PORT_PJ,
        GPIO_PIN4 | GPIO_PIN5,
        GPIO_PRIMARY_MODULE_FUNCTION);

    CS_turnOnLFXT(
        CS_LFXT_DRIVE_3);

    RTC_C_clearInterrupt(RTC_C_BASE,
                         RTC_C_CLOCK_READ_READY_INTERRUPT);

    RTC_C_enableInterrupt(RTC_C_BASE,
                          RTC_C_CLOCK_READ_READY_INTERRUPT);

    RTC_C_startClock(RTC_C_BASE);
}

//开机中断
#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector = PORT2_VECTOR
__interrupt
#elif defined(__GNUC__)
__attribute__((interrupt(PORT2_VECTOR)))
#endif
    void
    Port2Vector(void)
{
  kp2_time = rtc_sec;
  if (lcd_on == 0)
    lcd_on = 1;
  LED_RED_ON;

  GPIO_clearInterrupt(
      KP2_PORT,
      KP2_PIN);
  __bic_SR_register_on_exit(LPM0_bits);
}

//关机
case KEY_LEFT_LONG:
		power_state = 0;
		__delay_cycles(8000000 * 2);
		WDTCTL = 0xDEAD;
		break;