如果我不配置TZ的IO口，只用软件触发TZ可以吗？

我使用的是28035，想用TZ停止电机，用软件触发TZ锁死pwm输出，但是使用了

    EPwm1Regs.TZFRC.bit.OST = 1;
    EPwm2Regs.TZFRC.bit.OST = 1;
    EPwm3Regs.TZFRC.bit.OST = 1;

之后，还是有PWM输出

TZ是这样初始化的

      EALLOW;
// CPU Halt Trip  
      EPwm1Regs.TZSEL.bit.CBC6=0x1;
      EPwm2Regs.TZSEL.bit.CBC6=0x1;
      EPwm3Regs.TZSEL.bit.CBC6=0x1;

      EPwm1Regs.TZSEL.bit.OSHT1   = 1;  //enable TZ1 for OSHT  
      EPwm2Regs.TZSEL.bit.OSHT1   = 1;  //enable TZ1 for OSHT      
      EPwm3Regs.TZSEL.bit.OSHT1   = 1;  //enable TZ1 for OSHT

// What do we want the OST/CBC events to do?
// TZA events can force EPWMxA
// TZB events can force EPWMxB

      EPwm1Regs.TZCTL.bit.TZA = TZ_FORCE_HI; // EPWMxA will go high
      EPwm1Regs.TZCTL.bit.TZB = TZ_FORCE_HI; // EPWMxB will go high
      
      EPwm2Regs.TZCTL.bit.TZA = TZ_FORCE_HI; // EPWMxA will go high
      EPwm2Regs.TZCTL.bit.TZB = TZ_FORCE_HI; // EPWMxB will go high
      
      EPwm3Regs.TZCTL.bit.TZA = TZ_FORCE_HI; // EPWMxA will go high
      EPwm3Regs.TZCTL.bit.TZB = TZ_FORCE_HI; // EPWMxB will go high
            
      EDIS;

     // Clear any spurious OV trip
      EPwm1Regs.TZCLR.bit.OST = 1;
      EPwm2Regs.TZCLR.bit.OST = 1;
      EPwm3Regs.TZCLR.bit.OST = 1;