msp430x54x_ta_03.c

来自「MSP430的开发程序的例子+中文注释」· C语言 代码 · 共 52 行

//******************************************************************************
//  msp430FG5438 Demo - Timer_A, Toggle P1.0, Overflow ISR, DCO SMCLK
//
//  Description: Toggle P1.0 using software and Timer_A overflow ISR.
//  In this example an ISR triggers when TA overflows. Inside the TA
//  overflow ISR P1.0 is toggled. Toggle rate is approximatlely 16.8Hz.
//  Proper use of the TAIV interrupt vector generator is demonstrated.
//  ACLK = n/a, MCLK = SMCLK = TACLK = default DCO ~1.05MHz
//
//           msp430FG5438
//         ---------------
//     /|\|               |
//      | |               |
//      --|RST            |
//        |               |
//        |           P1.0|-->LED
//
//   M Smertneck
//   Texas Instruments Inc.
//   April 2008
//   Built with CCEv3.2 IAR Embedded Workbench Version: 3.42A
//******************************************************************************

#include <msp430x54x.h>

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  P1DIR |= 0x01;                            // P1.0 output
  TA0CTL = TASSEL_2 + MC_2 + TAIE;                // SMCLK, contmode, interrupt

  _BIS_SR(LPM0_bits + GIE);                 // Enter LPM0 w/ interrupt
}

// Timer_A3 Interrupt Vector (TAIV) handler
#pragma vector=TIMER0_A1_VECTOR
__interrupt void Timer_A(void)
{
 switch( TA0IV )
 {
   case  2: break;                          // CCR1 not used
   case  4: break;                          // CCR2 not used
   case  6: break;                          // CCR3 not used
   case  8: break;                          // CCR4 not used
   case  10: break;                         // CCR5 not used
   case  12: break;                         // CCR2 not used
   case  14: P1OUT ^= 0x01;                 // overflow
            break;
 }
}