USB⺯ʹ˵
1ʹôѹеUSB⺯ûвҪٶ
   USER_DEVICEDESCUSER_PRODUCTDESCUSER_STCISPCMDж
   Ѷ壬ɾ
2USBĬϵĲͣΪ@STCISP#
3USB⺯ֲѯжϿ⣬ͳһΪͬһ
   ʹset_usb_OUT_callbackûصʱʵжģʽ
   ûصΪѯģʽο
4ʹµUSBĿ⺯ҪȴUSBɣ
   printf_usbUSB_SendDataһ״̬æ־˼
5еĵԽӿںUSB_SendDataǻϽзװ
6printf_usb֧keil׼printfֵ֧ȫʽַ