ccs中 G2553.串口接受中断，为何进不去？，通过上位机调试也无法进入，求解释。

中断程序

void CH376_PORT_INIT( void ) /* 由于使用异步串口读写时序,所以进行初始化 */
{
DCOCTL = 0; // Select lowest DCOx and MODx settings
BCSCTL1 = CALBC1_1MHZ; // Set DCO
DCOCTL = CALDCO_1MHZ;
P1SEL = BIT1 + BIT2 ; // P1.1 = RXD, P1.2=TXD
P1SEL2= BIT1 + BIT2 ; // P1.1 = RXD, P1.2=TXD
UCA0CTL1 |= UCSSEL_2; // SMCLK波特率发生时钟
UCA0BR0 = 104; // 1MHz 9600 波特率发生器分频系数低八位
UCA0BR1 = 0; // 1MHz 9600 波特率发生器分频系数高八位
UCA0MCTL = UCBRS0; // Modulation UCBRSx = 1
UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine** 系统复位
IE2 |= UCA0RXIE; // Enable USCI_A0 RX interrupt 开启接受中断
_EINT();
}

#pragma vector=USCIAB0RX_VECTOR
__interrupt void USCI0RX_ISR(void)
{
while (!(IFG2&UCA0TXIFG)); // USCI_A0 TX buffer ready?
UCA0TXBUF = UCA0RXBUF; // TX -> RXed character
}

求解释，拜托了。

step by step：

你好，

     下面是2553的uart范例程序，建议先试试下面的程序能否进入中断，然后再对比一下你的程序来调试

#include <msp430.h>

int main(void){ WDTCTL = WDTPW + WDTHOLD; // Stop WDT if (CALBC1_1MHZ==0xFF) // If calibration constant erased { while(1); // do not load, trap CPU!! } DCOCTL = 0; // Select lowest DCOx and MODx settings BCSCTL1 = CALBC1_1MHZ; // Set DCO DCOCTL = CALDCO_1MHZ; P1SEL = BIT1 + BIT2 ; // P1.1 = RXD, P1.2=TXD P1SEL2 = BIT1 + BIT2 ; // P1.1 = RXD, P1.2=TXD UCA0CTL1 |= UCSSEL_2; // SMCLK UCA0BR0 = 104; // 1MHz 9600 UCA0BR1 = 0; // 1MHz 9600 UCA0MCTL = UCBRS0; // Modulation UCBRSx = 1 UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine** IE2 |= UCA0RXIE; // Enable USCI_A0 RX interrupt

__bis_SR_register(LPM0_bits + GIE); // Enter LPM0, interrupts enabled}

// Echo back RXed character, confirm TX buffer is ready first#pragma vector=USCIAB0RX_VECTOR__interrupt void USCI0RX_ISR(void){ while (!(IFG2&UCA0TXIFG)); // USCI_A0 TX buffer ready? UCA0TXBUF = UCA0RXBUF; // TX -> RXed character}