pagetotal.blogg.se

Each Input, Output, Feature, and/or Collection data item within a Collection item can be assigned a purpose with its own usage item. Usages identify the purpose of a collection and the items it contains. This is accomplished by the hierarchical assignment of usage information to collections. Usages are also used to define the meaning of groups of related data items. The HID Usage Tables 1.22 document defines constants that can be interpreted by an application to identify the purpose and meaning of a data field in a HID report.

be self-describing to allow generic software applications.

allow the software application to skip unknown information.

be as compact as possible to save device data space.

The primary and underlying goals of the HID class definition are to:

It also specifies how the HID class driver should extract data from USB devices.

The Device Class Definition for HID 1.11 is intended to supplement the USB Specification and provide HID manufacturers with the information necessary to build USB-compatible devices. HID Related Specifications and Tools Device Class Definition HID