AC97(4)                   OpenBSD Programmer's Manual                  AC97(4)

NAME
     ac97 - generic AC-97 codec driver

DESCRIPTION
     AC-97 codecs contain the analog-to-digital (A/D), digital-to-analog
     (D/A), and mixing circuitry of many modern sound cards.  AC-97 codecs,
     for the most part, do not talk to host busses like the PCI bus directly.
     Instead, they communicate through an interface chip, called the host con-
     troller.  The Ensoniq AudioPCI 97 (see eap(4)) is an example of such a
     host controller.

     Unlike many drivers, the ac97 driver does not appear in the configuration
     file.  Instead, the driver is automatically attached by the drivers that
     require it.

SEE ALSO
     auich(4), auvia(4), clcs(4), eap(4), fms(4), neo(4).

BUGS
     The ac97 driver does not keep track of the current user settings and in-
     stead relies on the hardware to do this.

     The ac97 driver could do more to detect mixer channels that don't work
     and cull them from the list.

OpenBSD 2.9                     October 7, 1999                              1
