Input Terminal Types USB Terminal IDīidirectional Terminal Types USB Terminal ID The following six tables show the terminal type identifiers and their corresponding pin category GUIDs. The header file Ksmedia.h defines a mapping for each USB terminal type identifier to a KS pin category GUID. When constructing a KS filter to represent a USB audio device, the USBAudio class system driver translates the terminals on the device into pins on the filter. For more information about pin descriptors, see Pin Factories.Ī USB audio device has some number of terminals through which digital streams and analog signals can enter and exit the device. Upon receiving a KSPROPERTY_PIN_CATEGORY property request from a client, the port driver retrieves the pin category GUID from the miniport driver's pin descriptor for the specified pin type. Each pin descriptor is a PCPIN_DESCRIPTOR structure containing an embedded KSPIN_DESCRIPTOR structure with a pin category GUID. In the case of a wave audio device on an internal bus (for example, PCI), the PortCls miniport driver contains an array of pin descriptors, each of which describes a pin type in the filter that represents the device. For example, a particular pin category GUID, KSNODETYPE_HEADPHONES, identifies a pin as an output jack for headphones. This GUID indicates the general category of functionality that the pin provides. A request for this property retrieves the KS pin category GUID from the KSPIN_DESCRIPTOR structure's Category member. Among those properties is the KSPROPERTY_PIN_CATEGORY property. ![]() Within this structure, the driver stores the KSPROPSETID_Pin properties of the pin type. ![]() A WDM audio driver maintains one KSPIN_DESCRIPTOR structure for each pin type that it supports. Microsoft Windows Driver Model (WDM) audio drivers for USB audio devices, IEEE 1394 audio devices, and audio devices on internal buses all represent their devices as KS filters with pins.
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