#include "msp430x54x.h" void main(void)
{ WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  P5SEL |=BIT6+BIT7;                        //USCI_A1 TXD/RXD
  P5DIR |=BIT5+BIT6;
  P5OUT &=~BIT5;
 
  UCA1CTL1 |= UCSWRST;                      // **Put state machine in reset**
  UCA1CTL1 |= UCSSEL_1;                     // CLK = ACLK
  UCA1BR0 = 0x03;                           // 32kHz/9600=3.41 (see User's Guide)
  UCA1BR1 = 0x00;                           //
  UCA1MCTL = UCBRS_3+UCBRF_0;               // Modulation UCBRSx=3, UCBRFx=0
  UCA1CTL1 &= ~UCSWRST;                     // **Initialize USCI state machine**
  UCA1IE |= UCRXIE+UCTXIE;                         // Enable USCI_A0 RX interrupt   __bis_SR_register(LPM3_bits + GIE);       // Enter LPM3, interrupts enabled
  __no_operation();                         // For debugger
} // Echo back RXed character, confirm TX buffer is ready first
#pragma vector=USCI_A1_VECTOR
__interrupt void USCI_A1_ISR(void)
{
  switch(__even_in_range(UCA1IV,4))
  {
  case 0:break;                             // Vector 0 - no interrupt
  case 2:                                   // Vector 2 - RXIFG
    while (!(UCA1IFG&UCTXIFG));             // USCI_A1 TX buffer ready?
    UCA1TXBUF = UCA1RXBUF;                  // TX -> RXed character
    P5OUT |=BIT5;
    while (!(UCA1IFG&UCTXIFG));
    P5OUT &=~BIT5;
    break;
  case 4:break;                             // Vector 4 - TXIFG
  default: break; 
  }
}
这是用TI的一个例程改的程序，只是将232改为485而已，但MCU总是停在低功耗状态无法进入中断或者停在红 {MOD}语句处，一步一步调试时只能进行一次中断，但串口助手无数据显示，已经检查过引脚，没有问题的，不知道哪里出错了，请高手指教 此帖出自小平头技术问答