AC97(4) 						   BSD Kernel Interfaces Manual 						   AC97(4)

NAME

     ac97 -- generic AC97 codec driver

DESCRIPTION

     AC97 codecs contain the analog-to-digital (A/D), digital-to-analog (D/A), and mixing circuitry of many modern sound cards.  AC97 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
     controller.  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

     auacer(4), auich(4), auixp(4), autri(4), auvia(4), clcs(4), clct(4), eap(4), emuxki(4), esa(4), esm(4), fms(4), neo(4), yds(4)

BUGS

     The ac97 driver does not keep track of the current user settings and instead 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.

BSD
								  October 7, 1999							       BSD