Overview

This chapter shows how to use the Human Input Device (HID) model in Windows. It is easy to write a user mode application to talk to a HID device through the Windows HID class driver. If need be, you can write a kernel mode HID client to do the same job. A HID kernel mode client can be layered over the HID class driver in the normal way. Alternatively, it can use Plug and Play Notification to find any suitable HID devices. Windows provides routines that make it much easier to analyze HID Report descriptors and send and receive reports.

This chapter initially looks at how to write a user mode application, called HidKbdUser, to talk to a HID keyboard. This section describes all the Windows parsing routines that are available to both user mode and kernel mode HID clients.

Later, the HidKbd kernel mode HID client driver is described. This illustrates the Plug and Play Notification technique of finding all devices with a matching device interface. HidKbd finds any devices with a HID class driver device interface. If a HID keyboard is found, it makes a device called \\.\HidKbd available to user mode applications. The HidKbdTest application tests the HidKbd driver.

HID Class Driver

The HID class driver is the key to using HID in Windows. It uses HID minidrivers to talk to actual devices. It handles requests from clients, directing them to the correct minidriver.

When a new HID device...