CS4299

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Revision as of 22:56, 30 November 2005 by 80.42.236.205 (Talk) (Dmixing)
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CS4299

This is a Cirrus Logic AC'97 Audio controller

This chip is sometimes incorrectly called CS4229 in IBM documentation

Features

  • Chipset: CS4299
  • Interface: AC'97 2.1

Linux OSS driver

This sound chip is supported by the i810_audio kernel module.

Linux ALSA driver

This sound chip is supported by the snd-intel8x0 kernel module.

Dmixing

The CS4299 is not capable of hardware mixing. This means that only one sound stream can be played at any time. You must get the software to do the mixing for it (this will load your CPU). The ALSA implementation of this is called DMIX. You can also run sound servers like ESD or ArtsD, but not all software will use them. Recent ALSA distributions have dmixing setup and enabled by default.

Otherwise just add the following to /etc/asound.conf :

  pcm.dsp0 {
      type plug
      slave.pcm dmix
  }
  # mixer0 can stay unchanged, because
  # it isn't used anyway, I guess ;)
  ctl.mixer0 {
      type hw
      card 0
  }


Now the only problem is how to tell applications to use the DMIX channel.

ThinkPads this chip may be found in