In addition, hardware vendors can choose to write custom device drivers that use one or both of these DDIs to manage their audio and modem codecs. In Windows Vista, Windows Server 2003 and Windows XP, the UAA class driver uses the DDI defined by the HDAUDIO_BUS_INTERFACE structure to manage UAA-compliant audio codecs. In Windows Vista, the HD Audio bus driver supports the DDI that is defined by the HDAUDIO_BUS_INTERFACE and the HDAUDIO_BUS_INTERFACE_V2 structures. The differences between the three DDIs are minor and are discussed in Differences Between the HD Audio DDI Versions.

This DDI is available in Windows XP and later versions of Windows. This DDI is available in Windows Vista and later versions of Windows.Ī DDI that is defined by the HDAUDIO_BUS_INTERFACE_BDL structure. This DDI is identical to the HD Audio DDI in Windows Vista.Ī DDI that is defined by the HDAUDIO_BUS_INTERFACE_V2 structure. The version of the HD Audio bus driver that runs on Windows Server 2003 and Windows XP supports three variants of the HD Audio DDI:Ī DDI that is defined by the HDAUDIO_BUS_INTERFACE structure. The HD Audio bus driver exposes the HD Audio DDI to its children, which are instances of the audio and modem drivers that manage the codecs. The HD Audio bus driver implements the HD Audio device driver interface (DDI), which kernel-mode audio and modem drivers use to communicate with hardware codecs that are attached to the HD Audio controller.

For an overview of Microsoft's UAA, see the white paper Universal Audio Architecture website.

For information about the HD Audio controller architecture, see the Intel High Definition Audio Specification at the Intel HD Audio website. Microsoft also will develop a similar HD Audio bus driver and UAA HD Audio class driver for systems that run Windows Server 2003, and Windows XP. In Windows Vista, Microsoft will provide the following two drivers as part of the operating system:Ī bus driver for managing an Intel High Definition Audio (HD Audio) bus interface controller.Ī Universal Audio Architecture (UAA) class driver for managing a UAA-compliant audio codec (or possibly more than one codec) that is connected to an HD Audio controller.

High definition audio device