FR6989跑eusci_a_uart串口例程时，不进入串口中断

使用MSP430FR6989 LaunchPad， 连接P2.0和P2.1，其他没有变化，跑例程时没有进入中断，麻烦谁能给解释一下是什么问题吗？

#include "driverlib.h"

uint16_t i;
uint8_t RXData = 0, TXData = 0;
uint8_t check = 0;

void main(void)
{
    // stop watchdog
    WDT_A_hold(WDT_A_BASE);

    // LFXT Setup
    //Set PJ.4 and PJ.5 as Primary Module Function Input.
    /*

     * Select Port J
     * Set Pin 4, 5 to input Primary Module Function, LFXT.
     */
    GPIO_setAsPeripheralModuleFunctionInputPin(
        GPIO_PORT_PJ,
        GPIO_PIN4 + GPIO_PIN5,
        GPIO_PRIMARY_MODULE_FUNCTION
        );

    //Set DCO frequency to 1 MHz
    CS_setDCOFreq(CS_DCORSEL_0,CS_DCOFSEL_0);
    //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);

    // Configure UART pins
    //Set P2.0 and P2.1 as Secondary Module Function Input.
    /*

     * Select Port 2d
     * Set Pin 0, 1 to input Secondary Module Function, (UCA0TXD/UCA0SIMO, UCA0RXD/UCA0SOMI).
     */
    GPIO_setAsPeripheralModuleFunctionInputPin(
        GPIO_PORT_P2,
        GPIO_PIN0 + GPIO_PIN1,
        GPIO_SECONDARY_MODULE_FUNCTION
        );

    /*
     * Disable the GPIO power-on default high-impedance mode to activate
     * previously configured port settings
     */
    PMM_unlockLPM5();

    // Configure UART
    EUSCI_A_UART_initParam param = {0};
    param.selectClockSource = EUSCI_A_UART_CLOCKSOURCE_ACLK;
    param.clockPrescalar = 3;
    param.firstModReg = 0;
    param.secondModReg = 92;
    param.parity = EUSCI_A_UART_NO_PARITY;
    param.msborLsbFirst = EUSCI_A_UART_LSB_FIRST;
    param.numberofStopBits = EUSCI_A_UART_ONE_STOP_BIT;
    param.uartMode = EUSCI_A_UART_MODE;
    param.overSampling = EUSCI_A_UART_LOW_FREQUENCY_BAUDRATE_GENERATION;

    if(STATUS_FAIL == EUSCI_A_UART_init(EUSCI_A0_BASE, &param))
    {
        return;
    }

    EUSCI_A_UART_enable(EUSCI_A0_BASE);

    EUSCI_A_UART_clearInterrupt(EUSCI_A0_BASE,
                                EUSCI_A_UART_RECEIVE_INTERRUPT);

    // Enable USCI_A0 RX interrupt
    EUSCI_A_UART_enableInterrupt(EUSCI_A0_BASE,
                                 EUSCI_A_UART_RECEIVE_INTERRUPT); // Enable interrupt

    __enable_interrupt();
    while(1)
    {
        TXData = TXData + 1;                      // Increment TX data
        // Load data onto buffer
        EUSCI_A_UART_transmitData(EUSCI_A0_BASE,
                                  TXData);
        while(check != 1)
        {
            ;
        }
        check = 0;
    }
}

//******************************************************************************
//
//This is the USCI_A0 interrupt vector service routine.
//
//******************************************************************************
#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=USCI_A0_VECTOR
__interrupt
#elif defined(__GNUC__)
__attribute__((interrupt(USCI_A0_VECTOR)))
#endif
void USCI_A0_ISR(void)
{
    switch(__even_in_range(UCA0IV,USCI_UART_UCTXCPTIFG))
    {
    case USCI_NONE: break;
    case USCI_UART_UCRXIFG:
        RXData = EUSCI_A_UART_receiveData(EUSCI_A0_BASE);
        if(!(RXData == TXData))                 // Check value
        {
            while(1)
            {
                ;
            }
        }
        check = 1;
        break;
    case USCI_UART_UCTXIFG: break;
    case USCI_UART_UCSTTIFG: break;
    case USCI_UART_UCTXCPTIFG: break;
    }
}