HID Usages
HID usages identify the intended use of HID controls and what the controls actually measure.
The following concepts and terminology are used throughout the HID documentation in the WDK:
For specific examples of usages that Windows components access, see Top-Level Collections Opened by Windows for System Use.
For more information about how to determine the usages that a HIDClass device supports, see:
For detailed information about industry standard HID usage, see the Universal Serial Bus (USB) specification HID Usage Tables that is located at the USB Implementers Forum website.
Usage page
HID usages are organized into usage pages of related controls. A specific control usage is defined by its usage page, a usage ID, a name, and a description. A usage page value is a 16-bit unsigned value.
Examples of usage pages include:
| Page ID | Page Name | hidusage.h constant |
|---|---|---|
| 0x01 | Generic Desktop Controls | HID_USAGE_PAGE_GENERIC |
| 0x05 | Game Controls | HID_USAGE_PAGE_GAME |
| 0x08 | LEDs | HID_USAGE_PAGE_LED |
| 0x09 | Button | HID_USAGE_PAGE_BUTTON |
Usage ID
In the context of a usage page, a valid usage identifier, or usage ID, indicates a usage in a usage page. A usage ID of zero is reserved. A usage ID value is an unsigned 16-bit value.
Examples of controls that are listed on the Generic Desktop Controls usage page:
| Usage ID | Usage Name | hidusage.h constant |
|---|---|---|
| 0x01 | Pointer | HID_USAGE_GENERIC_POINTER |
| 0x02 | Mouse | HID_USAGE_GENERIC_MOUSE |
| 0x04 | Joystick | HID_USAGE_GENERIC_JOYSTICK |
| 0x05 | Game Pad | HID_USAGE_GENERIC_GAMEPAD |
| 0x06 | Keyboard | HID_USAGE_GENERIC_KEYBOARD |
| 0x07 | Keypad | HID_USAGE_GENERIC_KEYPAD |
| 0x08 | Multi-axis Controller | HID_USAGE_GENERIC_MULTI_AXIS_CONTROLLER |
Extended usage
An extended usage is a 32-bit value that specifies a 16-bit usage page value in the most-significant two bytes and a 16-bit usage ID in the least significant two bytes of the extended usage value.
Usage range
A usage range is an inclusive, consecutive range of usage IDs, all of which are on the same usage page. A usage range is specified by usage minimum and usage maximum items in a report descriptor.
Aliased usages
More than one usage can be specified for a link collection or a HID control. For a given collection or control, a group of such usages are aliases of one another, and are referred to as aliased usages. Delimiter items are used to specify aliased usages. Usage ranges cannot be aliased.
For information about how aliased usages are specified in a top-level collection's capability arrays, see Button Capability Arrays and Value Capability Arrays.