msp430g2553的I2C通信，

只看该作者 · 2013-7-31 12:31

官网给的的主机发送例程，调试时候停在开低功耗之后，始终没有触发发送中断，求指点迷津
#include "msp430g2553.h"

unsigned char TXData;
unsigned char TXByteCtr;

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                // Stop WDT
  P1SEL |= BIT6 + BIT7;                   // Assign I2C pins to USCI_B0
  P1SEL2|= BIT6 + BIT7;                   // Assign I2C pins to USCI_B0
  UCB0CTL1 |= UCSWRST;                   // Enable SW reset
  UCB0CTL0 = UCMST + UCMODE_3 + UCSYNC;    // I2C Master, synchronous mode
  UCB0CTL1 = UCSSEL_2 + UCSWRST;          // Use SMCLK, keep SW reset
  UCB0BR0 = 12;                            // fSCL = SMCLK/12 = ~100kHz
  UCB0BR1 = 0;
  UCB0I2CSA = 0x48;                      // Slave Address is 048h
  UCB0CTL1 &= ~UCSWRST;                   // Clear SW reset, resume operation
  IE2 |= UCB0TXIE;                         // Enable TX interrupt

  TXData = 0x00;                         // Holds TX data

  while (1)
  {
TXByteCtr = 1;                         // Load TX byte counter
while (UCB0CTL1 & UCTXSTP);          // Ensure stop condition got sent
UCB0CTL1 |= UCTR + UCTXSTT;          // I2C TX, start condition
__bis_SR_register(CPUOFF + GIE);       // Enter LPM0 w/ interrupts
                                          // Remain in LPM0 until all data
                                          // is TX'd
TXData++;                            // Increment data byte
  }
}

//------------------------------------------------------------------------------
// The USCIAB0TX_ISR is structured such that it can be used to transmit any
// number of bytes by pre-loading TXByteCtr with the byte count.
//------------------------------------------------------------------------------
#pragma vector = USCIAB0TX_VECTOR
__interrupt void USCIAB0TX_ISR(void)
{
  if (TXByteCtr)                         // Check TX byte counter
  {
UCB0TXBUF = TXData;                   // Load TX buffer
TXByteCtr--;                         // Decrement TX byte counter
  }
  else
  {
UCB0CTL1 |= UCTXSTP;                   // I2C stop condition
IFG2 &= ~UCB0TXIFG;                   // Clear USCI_B0 TX int flag
__bic_SR_register_on_exit(CPUOFF);    // Exit LPM0
  }
}