Download WinDriver v6.20 User`s Guide

WinDriver v6.20 User’s Guide
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device descriptor identifies, among other things, the device class (HID device,
hub, locator device, etc.), subclass, protocol code, vendor ID, device ID and
more. Each USB device has one device descriptor.
Configuration Level: A USB device has one or more configuration descriptors.
Each descriptor identifies the number of interfaces grouped in the configuration
and the power attributes of the configuration (such as self-powered, remote
wakeup, maximum power consumption and more). Only one configuration
can be loaded at a given time. For example, an ISDN adapter might have two
different configurations, one that presents it with a single interface of 128 Kbps
and a second that presents it with two interfaces of 64 Kbps each.
Interface Level: The interface is a related set of endpoints that present a specific
functionality or feature of the device. Each interface may operate independently.
The interface descriptor describes the number of the interface, the number of
endpoints used by this interface and the interface-specific class, subclass and
protocol values when the interface operates independently. In addition, an
interface may have alternate settings. The alternate settings allow the endpoints
or their characteristics to be varied after the device is configured.
Endpoint Level: The lowest level is the endpoint descriptor that provides the
host with information regarding the data transfer type of the endpoint and
the bandwidth of each endpoint (the maximum packet size of the specific
endpoint). For isochronous endpoints, this value is used to reserve the bus time
required for the data transfer. Other attributes of the endpoints are their bus
access frequency, their endpoint number, their error handling mechanism and
their direction.
Seems complicated? Not at all! WinDriver automates the USB configuration process.
The included DriverWizard and USB diagnostics application scan the USB bus,
detect all USB devices and their configurations, interfaces, settings and endpoints,
and enable the developer to pick the desired configuration before starting driver
development.
WinDriver identifies the endpoint transfer type as determined in the endpoint
descriptor. The driver created with WinDriver contains all configuration information
acquired at this early stage.