fet140_tb05.c

msp430f14x 系列片内外设的实例代码

//******************************************************************************
//  MSP-FET430P140 Demo - Timer_B Toggle P1.0, CCR0 upmode ISR, 32kHz ACLK 
//
//  Description; Toggle P1.0 using software and the TB_0 ISR. Timer_B is 
//  configured to be in upmode, thus the the timer will overflow when TBR counts 
//  to TBCCR0. In this example, TBCCR0 is loaded with 1000-1.
//  Toggle rate = 32768/(2*1000) = 16.384
//  ACLK = TBCLK = 32kHz, MCLK = SMCLK = DCO~ 800k
//  //*An external watch crystal on XIN XOUT is required for ACLK*//	  
//   
//           MSP430F149
//         ---------------
//     /|\|            XIN|-  
//      | |               | 32kHz
//      --|RST        XOUT|-
//        |               |
//        |           P1.0|-->LED
//
//  M. Buccini
//  Texas Instruments, Inc
//  October 2003
//  Built with IAR Embedded Workbench Version: 1.26B
//  June 2004
//  Updated for IAR Embedded Workbench Version: 2.21B
//******************************************************************************

#include <msp430x14x.h>

void main(void)
{ 
  WDTCTL = WDTPW + WDTHOLD;             // Stop WDT
  P1DIR |= 0x01;                        // Set P1.0 to output direction
  TBCTL = TBSSEL_1 + TBCLR;             // ACLK, clear TBR
  TBCCTL0 = CCIE;                       // TRCCR0 interrupt enabled
  TBCCR0 = 1000-1;
  TBCTL = TBSSEL_1 + MC_1;              // ACLK, upmode
 
  _BIS_SR(LPM3_bits + GIE);             // Enter LPM3 w/ interrupt
}

// Timer B0 interrupt service routine
#pragma vector=TIMERB0_VECTOR
__interrupt void Timer_B (void)
{
    P1OUT ^= 0x01;                      // Toggle P1.0 using exclusive-OR
}