TI程序里对速度的计算程序求解释

ldj809

void speed_prd_calc(SPEED_MEAS_CAP *v)
{
   
   if (v->InputSelect == 0)  
   {
     v->OldTimeStamp = v->NewTimeStamp;
     v->NewTimeStamp = v->TimeStamp;
     v->EventPeriod = v->NewTimeStamp - v->OldTimeStamp; ///求出两脉冲之间的时间差
   
     if (v->EventPeriod < 0)
       v->EventPeriod += 32767;   // 0x7FFF = 32767
    }

     v->Speed = _IQdiv(v->SpeedScaler,v->EventPeriod); //？？？？？？？？？？？？？？
   v->SpeedRpm = _IQmpy(v->BaseRpm,v->Speed); ////???????????????????????
   
}

程序中
speed1.SpeedScaler = 60*(SYSTEM_FREQUENCY*1000000/1000)*1/(128*speed1.BaseRpm);
求大侠们帮忙看看打问号的两句是啥子意思来着，v->BaseRpm是额定频率（转/分）