About the audio subsystem

The audio subsystem consists of:

Audio device drivers

Modern audio adapters (and sound controllers integrated on the motherboard) often comprise a set of independent devices. UnixWare 7 audio drivers support these devices:

• the basic device for digital/analog conversion. This allows digital sound files to be converted to analog signals for playback, and analog signals from a recording device to be stored digitally.

• synthesizers, used for playing music

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  NOTE: Only FM synthesizers are currently supported.

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• MIDI (Musical Instrument Digital Interface) interfaces, used to connect external electronic musical instruments to a computer

Each of these devices requires its own I/O address and other configuration parameters. See also ``Audio device entries in the Resource Manager database''.

Play and record utilities

Computer audio subsystems must include software to control input and output sound characteristics such as volume levels, stereo separation, and sound sources. Sound-enabled applications often include such capabilities, which can communicate directly with the audio driver.

UnixWare 7 includes the scosound(X1) utility for playing and recording sounds. UnixWare 7 also includes these command-line utilities:

mixer(1)

sets volume levels, and selects input and output devices

vplay(1)

plays sound files

vrec(1)

records sound files

An audio driver must be installed before these utilities can be used.

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NOTE: Volume levels must be set manually with mixer before using scosound, or a command line must be available to run mixer in addition to running scosound.

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UnixWare 7 audio adapters drivers are based on Open Sound System (OSS), a sound driver architecture for UNIX systems developed by 4Front Technologies. Because the SCO audio subsystem conforms to the OSS API (Application Programming Interface), you can run OSS-compliant audio-enabled applications on SCO systems. For more information and examples of audio-enabled applications, see their web site:

http://www.4front-tech.com/.

However, the 4Front sound drivers included in Skunkware are not supported on UnixWare 7 systems; see ``Compatibility with earlier SCO audio drivers''.