pwm不进中断也有输出的问题

w zh

我调试中遇到的问题是，当我屏蔽掉主程序中的 PieCtrlRegs.PIEIER3.bit.INTx1 = 1;和 PieVectTable.EPWM1_INT = &EPWM1_INT_ISR;时，28335也能输出方波。我明明是设置了中断模式的，怎么会不进中断也有数据输出呢？

另外正常进中断时，用示波器测量28335的输出波形，每产生7.5ms的方波，就有2.5ms的低电平。如果不进中断，则一直有方波输出，没有长时间的低电平。请问，为什么会出现这种情况？

请高手予以指教，谢谢！

我的程序如下：

void main(void)
{

     InitSysCtrl();

     EALLOW;

     InitEPwm1Gpio();

      DINT;
     InitPieCtrl();

// Disable CPU interrupts and clear all CPU interrupt flags:
     IER = 0x0000;
     IFR = 0x0000;

     InitPieVectTable();

     EALLOW;
     PieVectTable.EPWM1_INT = &EPWM1_INT_ISR;


     EDIS;

    EALLOW;
     SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 0;
     EDIS;

     HRPWM1_Config(3750);


     EALLOW;
     SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1;
     EDIS;

     IER = M_INT3 ;

     PieCtrlRegs.PIEIER3.bit.INTx1 = 1;

     EINT;
     ERTM;

        for(;;);

}

void HRPWM1_Config(period)
{
     EPwm1Regs.TBPRD = period;
     EPwm1Regs.TBPHS.half.TBPHS = 0x0000;
     EPwm1Regs.TBCTR = 0x0000;

      EPwm1Regs.CMPA.half.CMPA = 1500;

     EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN;
     EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE;
     EPwm1Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1;
     EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV1;

     EPwm1Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;
     EPwm1Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO_PRD;

     EPwm1Regs.AQCTLA.bit.CAD = AQ_SET;
     EPwm1Regs.AQCTLA.bit.CAU = AQ_CLEAR;

     EPwm1Regs.ETSEL.bit.INTSEL = ET_CTR_ZERO; //1,Enable event time-base counter equal to zero.(TBCTR = 0x0000)
     EPwm1Regs.ETSEL.bit.INTEN = 1; //Enable EPWMx_INT generation
    EPwm1Regs.ETPS.bit.INTPRD = ET_3RD; //1,Generate an interrupt on the first event INTCNT = 01 (first event)

    EPwm1Regs.ETCLR.bit.INT=1; //清楚中断标志位

     EPwm1Regs.DBCTL.all = 0xb;
        EPwm1Regs.DBRED=60;                                                // Dead-band rising edge delay
        EPwm1Regs.DBFED=60;                                              // Dead-band falling edge delay

}

// INT 3.1
interrupt void EPWM1_INT_ISR(void)     // EPWM-1
{

   if(k >= PRD)
      {
        k = 0;
      }

   EPwm1Regs.CMPA.half.CMPA = (Uint32)TonC[k];
   k++;

   EPwm1Regs.ETCLR.bit.INT = 1; //Clears the ETFLG[INT] flag bit and enable further interrupts pulses to be generated
   PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;

}