main.c

MSP430FG4618简单串口通信程序

//******************************************************************************
//   MSP430xG46x Demo - USCI_A0, Ultra-Low Pwr UART 9600 Echo ISR, 32kHz ACLK
#include  "msp430xG46x.h"

void main(void)
{
  volatile unsigned int i;

  WDTCTL = WDTPW+WDTHOLD;                   // Stop WDT
  FLL_CTL0 |= XCAP14PF;                     // Configure load caps

  do
  {
  IFG1 &= ~OFIFG;                           // Clear OSCFault flag
  for (i = 0x47FF; i > 0; i--);             // Time for flag to set
  }
  while ((IFG1 & OFIFG));                   // OSCFault flag still set?
  P10DIR = 0XFF;
  P10OUT = 0X00;
  P2SEL |= 0x030;                           // P2.5,4 = USCI_A0 RXD/TXD
  UCA0CTL1 |= UCSSEL_1;                     // CLK = ACLK
  UCA0BR0 = 0x03;                           // 32k/9600 - 3.41
  UCA0BR1 = 0x00;                           //
  UCA0MCTL = 0x06;                          // Modulation
  UCA0CTL1 &= ~UCSWRST;                     // **Initialize USCI state machine**
  IE2 |= UCA0RXIE;                          // Enable USCI_A0 RX interrupt

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

//  Echo back RXed character, confirm TX buffer is ready first
#pragma vector=USCIAB0RX_VECTOR
__interrupt void USCIA0RX_ISR (void)
{
  while(!(IFG2&UCA0TXIFG));
  UCA0TXBUF = UCA0RXBUF;                    // TX -> RXed character
  P10OUT  = UCA0TXBUF;
}