求助

zzbaizhi

求助 [复制链接]

#include "msp430x54x.h"

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  P1DIR |= 0x01;                                                // P1.0 output
  TA1CTL = TASSEL_1 + MC_1 + TACLR + TAIE;  // ACLK,  clear TAR
  TA1CCR1= 5000;
  TA1CCR0= 65535;
  TA1CCTL1|=CCIE;                          

  __bis_SR_register(LPM3_bits + GIE);       // Enter LPM3, enable interrupts
  __no_operation();                                     // For debugger
}

 

 

// Timer_A3 Interrupt Vector (TAIV) handler
#pragma vector=TIMER1_A1_VECTOR
__interrupt void TIMER1_A1_ISR(void)
{
  switch(__even_in_range(TA1IV,14))
  {
    case  0: break;                          // No interrupt
    case  2: P1OUT ^= 0x01;                 
                 break;
    case  4: break;                          // CCR2 not used
    case  6: break;                          // reserved
    case  8: break;                          // reserved
    case 10: break;                          // reserved
    case 12: break;                          // reserved
    case 14: break;                 
    default: break;
  }
}

我的目的是利用捕获/比较模块1的中断来实现灯的闪烁，但改变TA1CCR1的值，灯闪烁频率未变，改变TA1CCR0的值，灯的闪烁频率改变，不知道错在哪

急~~

wstt

你同时开了CCR0和CCR1的中断，CCR0优先级高于CCR1，先响应CCR0再响应CCR1

[ 本帖最后由 wstt 于 2011-12-20 12:11 编辑 ]

peter_zheng

改变TA1CCR1改变的是PWM的占空比，改变TA1CCR0改变的是PWM的频率