想配置下lm3s9b92 的rom bootloader 启动管脚

我真的怀疑这里是否有TI的工程师，这个问题应该不算难，但是没有一个答复，真是心寒，还是撤吧

//use PB7 to active ROM bootloader

    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);

    GPIOPinTypeGPIOInput(GPIO_PORTB_BASE, GPIO_PIN_7);

    if (HWREG( FLASH_BOOTCFG )&FLASH_BOOTCFG_NW)

    {

    HWREG( FLASH_BOOTCFG)= 0x00003C01;

    HWREG(FLASH_FMD)    =     0x00003C01;

    HWREG(FLASH_FMA) = 0x75100000;

    HWREG(FLASH_FMC) = FLASH_FMC_WRKEY | FLASH_FMC_COMT;

    //

    // Wait until the write has completed.

    //

    while(HWREG(FLASH_FMC) & FLASH_FMC_COMT)

    {    }

    }