以下是USB初始化函数

void USB_Init(void)
{
  pInformation = &Device_Info;    //定义了一个实体结构
  pInformation->ControlState = 2;     //设置了内部变量
  pProperty = &Device_Property;     //定义了一个实体结构
  pUser_Standard_Requests = &User_Standard_Requests;   //定义了一个实体结构
  /* Initialize devices one by one */
  pProperty->Init();  //这个函数我知道是调用 pProperty的init()函数，可这个函数是空的啊，求大家不吝赐教！！！！！！！！！！
}

以下是上面那个 pProperty的结构体定义
typedef struct _DEVICE_PROP
{
  void (*Init)(void);        /* Initialize the device */
  void (*Reset)(void);       /* Reset routine of this device */

  /* Device dependent process after the status stage */
  void (*Process_Status_IN)(void);
  void (*Process_Status_OUT)(void);

  /* Procedure of process on setup stage of a class specified request with data stage */
  /* All class specified requests with data stage are processed in Class_Data_Setup
   Class_Data_Setup()
    responses to check all special requests and fills ENDPOINT_INFO
    according to the request
    If IN tokens are expected, then wLength & wOffset will be filled
    with the total transferring bytes and the starting position
    If OUT tokens are expected, then rLength & rOffset will be filled
    with the total expected bytes and the starting position in the buffer

    If the request is valid, Class_Data_Setup returns SUCCESS, else UNSUPPORT

   CAUTION:
    Since GET_CONFIGURATION & GET_INTERFACE are highly related to
    the individual classes, they will be checked and processed here.
  */
  RESULT (*Class_Data_Setup)(uint8_t RequestNo);

  /* Procedure of process on setup stage of a class specified request without data stage */
  /* All class specified requests without data stage are processed in Class_NoData_Setup
   Class_NoData_Setup
    responses to check all special requests and perform the request

   CAUTION:
    Since SET_CONFIGURATION & SET_INTERFACE are highly related to
    the individual classes, they will be checked and processed here.
  */
  RESULT (*Class_NoData_Setup)(uint8_t RequestNo);

  /*Class_Get_Interface_Setting
   This function is used by the file usb_core.c to test if the selected Interface
   and Alternate Setting (uint8_t Interface, uint8_t AlternateSetting) are supported by
   the application.
   This function is writing by user. It should return "SUCCESS" if the Interface
   and Alternate Setting are supported by the application or "UNSUPPORT" if they
   are not supported. */

  RESULT  (*Class_Get_Interface_Setting)(uint8_t Interface, uint8_t AlternateSetting);

  uint8_t* (*GetDeviceDescriptor)(uint16_t Length);
  uint8_t* (*GetConfigDescriptor)(uint16_t Length);
  uint8_t* (*GetStringDescriptor)(uint16_t Length);

  /* This field is not used in current library version. It is kept only for
   compatibility with previous versions */
  void* RxEP_buffer;
   
  uint8_t MaxPacketSize;

}DEVICE_PROP;



这个init函数执行到哪里去了？？？？