mc9s12xs128 帮助

竹本选

PWM  P0口 发出频率250hz
采用周期中断PIT 0.5ms ，计数IC0口的脉冲，然后求速度
但是调试不出速度，求帮助

#include <hidef.h>      /* common defines and macros */
#include "derivative.h"      /* derivative-specific definitions */
#include "w_speed.h"

#define  chishu  40  
#define  radius  262    //mm
#define  dt      500     //ms
int iPulesNum=0;
int temp=0;
int w_speed0=0;
void main(void) {
  /* put your own code here */

PWM4ms_Init();
CAP0_Init();
PIT0_Init();
EnableInterrupts;


  for(;;) {
  
  w_speed0=(temp*3*radius)/(dt*chishu);
  
    _FEED_COP(); /* feeds the dog */
  } /* loop forever */
  /* please make sure that you never leave main */
}
#pragma CODE_SEG __NEAR_SEG NON_BANKED
void interrupt 66 PIT0_ISR(void)
{

   temp= iPulesNum;
  
//  w_speed0=(temp*3*radius)/(dt*chishu);
   
   iPulesNum=0;
   PITTF_PTF0=1; //clear PIT ch 0 time-out flag
}
#pragma CODE_SEG __NEAR_SEG NON_BANKED
void  interrupt 8 capture0_ISR(void)
{
   TFLG1_C0F = 1;
   iPulesNum++;
}