关于GPIO的设置GPXDAT控制方式疑问

   EALLOW;
GpioCtrlRegs.GPBPUD.bit.GPIO32  = 0;  // Enable the internal pullup on the specified pin
GpioCtrlRegs.GPBMUX1.bit.GPIO32 = 0; // general purpose I/O
GpioCtrlRegs.GPBDIR.bit.GPIO32 = 1;  //Configures the GPIO pin as an output
GpioCtrlRegs.GPBPUD.bit.GPIO60  = 0;  // Enable the internal pullup on the specified pin
GpioCtrlRegs.GPBMUX2.bit.GPIO60 = 0; // general purpose I/O
GpioCtrlRegs.GPBDIR.bit.GPIO60 = 1;  //Configures the GPIO pin as an output
GpioCtrlRegs.GPBPUD.bit.GPIO61  = 0;  // Enable the internal pullup on the specified pin
GpioCtrlRegs.GPBMUX2.bit.GPIO61 = 0; // general purpose I/O
GpioCtrlRegs.GPBDIR.bit.GPIO61 = 1;  //Configures the GPIO pin as an output
EDIS;
#if 1  //gpio60对应的LED不闪烁
  GpioDataRegs.GPBDAT.bit.GPIO32 =0;
  GpioDataRegs.GPBDAT.bit.GPIO60 =0;
  GpioDataRegs.GPBDAT.bit.GPIO61 =0;
  DSP28x_usDelay(10000000);
  GpioDataRegs.GPBDAT.bit.GPIO32 =1;
  GpioDataRegs.GPBDAT.bit.GPIO60 =1;
  GpioDataRegs.GPBDAT.bit.GPIO61 =1;
  DSP28x_usDelay(10000000);
#endif
#if 0
  GpioDataRegs.GPBSET.bit.GPIO32 =1;
  GpioDataRegs.GPBSET.bit.GPIO60 =1;
  GpioDataRegs.GPBSET.bit.GPIO61 =1;
  DSP28x_usDelay(10000000);
  GpioDataRegs.GPBCLEAR.bit.GPIO32 =1;
  GpioDataRegs.GPBCLEAR.bit.GPIO60 =1;
  GpioDataRegs.GPBCLEAR.bit.GPIO61 =1;
  DSP28x_usDelay(10000000);
#endif
#if 0
  GpioDataRegs.GPBTOGGLE.bit.GPIO32 =1;
  GpioDataRegs.GPBTOGGLE.bit.GPIO60 =1;
  GpioDataRegs.GPBTOGGLE.bit.GPIO61 =1;
  DSP28x_usDelay(10000000);
  GpioDataRegs.GPBTOGGLE.bit.GPIO32 =1;
  GpioDataRegs.GPBTOGGLE.bit.GPIO60 =1;
  GpioDataRegs.GPBTOGGLE.bit.GPIO61 =1;
  DSP28x_usDelay(10000000);
#endif

这三种方式中只有GPBDAT写0写1控制LED时GPIO60是常亮的。。
请问这是为什么？？