DSP28034的 GPIO32,GPIO33 无法拉低

这是引脚初始代码

void InitI2CGpio(void)
{

EALLOW;

GpioCtrlRegs.GPBPUD.bit.GPIO32 = 0; // Enable pull-up for GPIO32 (SDAA)
GpioCtrlRegs.GPBPUD.bit.GPIO33 = 0; // Enable pull-up for GPIO33 (SCLA)

 GpioCtrlRegs.GPBDIR.bit.GPIO32 =1;

GpioCtrlRegs.GPBDIR.bit.GPIO33 =1;

GpioCtrlRegs.GPBMUX1.bit.GPIO32 = 1; // Configure GPIO32 for SDAA operation
GpioCtrlRegs.GPBMUX1.bit.GPIO33 = 1; // Configure GPIO33 for SCLA operation

EDIS;

}

#define SDAA GpioDataRegs.GPBDAT.bit.GPIO32 // (SDAA)
#define SCLA GpioDataRegs.GPBDAT.bit.GPIO33 // (SCLA)

执行下面代码无法拉低

SCLA=0;
SDAA=0;