usb_config.h is a file used to configure the MCHPFSUSB stack and various function drivers. This file provides compile time selection of options provided by the stack. This file defines constants needed by the stack and various function drivers.
This section will detail the definitions required by vendor class function drivers. Additional definitions may be required by the stack itself. Please see the Files topic of the Stack section for more details about stack specific definitions.
Please note that the usb_config.h file can also be generated using the USBConfig.exe tool provided in the "<Install Directory>\USB Tools\USBConfig Tool" directory.
USB_USE_GEN - This define lets the USB stack know that it will be using a vendor class function driver. This should be defined for any device using a vendor class function driver.
#define USB_USE_GEN
USBGEN_EP_SIZE - this defines the size of the IN endpoint used by the MSD driver. The valid range is 1-64 for bulk endpoints and 1-1023 for Isochronous endpoints.
#define USBGEN_EP_SIZE 64
USBGEN_EP_NUM - This defines the endpoint number used by the driver. This number should be unique within the configuration.
#define USBGEN_EP_NUM 1