audio1575(7D) Devices audio1575(7D)
NAME
audio1575 - Uli M1575 Super South Bridge audio digital controller interface.
DESCRIPTION
The audio1575 device uses the Uli M1575 AC97-compatible audio digital controller and an AC-97 Codec to implement the audio device inter-
face. This interface allows analog only inputs and outputs.
API
This interface is described in the audio(7I) and mixer(7I) man pages.
Driver Versions
Applications that open /dev/audio may use the AUDIO_GETDEV ioctl(2) to determine which audio device is being used. The audio1575 driver
will return the string SUNW,audio1575 in the name field of the audio_device structure. The version field contains the letter a and the con-
fig field contains the string onboard1.
Platform Ver. Out H. Phone Speaker In Mic CD
Sun A70 Workstation a Y Y Y Y Y Y
Key to the above table: Ver = Version. Out = Line Out. Speaker = Internal Speaker. In = Line In. Mic. = Microphone. CD = CD-ROM.
The audio1575 device provides support for the internal speaker, headphone, line out, line in, and microphone. The play.mod_ports and
record.mod_ports fields of the audio_info structure (see audio(7I)) indicate which ports may be manipulated.
Audio Mixer Mode
This driver supports the mixer mode. Compat mode is supported only for Sampling Rate (8Khz-48Khz), Encoding (16 Bit linear (PCM)), and
Channels (Stereo) configurations.
Audio Data Formats
The audio1575 device natively supports 16-bit linear encodings in stereo. With the mixer enabled, a continuous range of sample rates from
8000 Hz to 48000 Hz is supported. With the mixer disabled, the same sample rates are supported but only for stereo 16 bit linear PCM encod-
ing. The device can be opened for simultaneous play and record whether the mixer is enabled or not.
Sample Granularity
Because the audio1575 device manipulates buffers of audio data, the reported input and output sample counts will vary at any time from the
actual sample count by no more than the size of the buffers the driver is transferring. Programs should not rely on the absolute accuracy
of the play.samples and record.samples fields of the audio_info structure.
Interrupt Rate
The driver determines how often play and record interrupts should occur. For playing audio, this determines how often and how much audio is
requested from the audio mixer. The impact of interrupts on recording is minimal, however, if a very small read buffer size is set, the
record interrupt rate should be increased to prevent the buffer from overflowing. You can tune the play and record interrupt rates using
the /kernel/drv/audio1575.conf file.
Audio Status Change Notification
As described in the audio(7I) and mixer(7I) man pages, it is possible to request asynchronous notification of changes in the state of an
audio device.
ERRORS
All audio1575 errors are described in the audio(7I) man pages.
FILES
/dev/audio
Symbolic link to the system's primary audio device (not necessarily an audio1575 device).
/dev/audioctl
Control device.
/dev/sound/0
Represents the first audio device on the system (not necessarily an audio1575 device).
/dev/sound/0ctl
Audio control.
/usr/share/audio/samples
Audio sample files.
/kernel/drv/audio1575.conf
Audio1575 driver configuration file.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+--------------------+--------------------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+--------------------------------------+
|Architecture |SPARC-based systems |
+--------------------+--------------------------------------+
|Availability |SUNWaudd, SUNWauda |
+--------------------+--------------------------------------+
|Stability level |Evolving |
+--------------------+--------------------------------------+
SEE ALSO
mixerctl(1), sdtaudiocontrol(1), ioctl(2), attributes(5), audio(7I), mixer(7I), streamio(7I)
Uli M1575 Super South Bridge Data Sheet Data Sheet-- Uli USA Inc.
AD1981B AC '97 SoundMAX(R) Codec Data Sheet-- Analog Devices Inc.
http://www.sun.com/io
DIAGNOSTICS
In addition to being logged, the following messages may appear on the system console:
init_state() play interrupt rate set too low.
The play interrupt rate specified in audio1575.conf is set too low. It has been reset to the rate specified in the message. Update
audio1575.conf to a higher play interrupt rate.
init_state() play interrupt rate set too high.
The play interrupt rate specified in audio1575.conf is set too high. It has been reset to the rate specified in the message. Update
audio1575.conf to a lower play interrupt rate.
init_state() record interrupt rate set too low.
The record interrupt rate specified in audio1575.conf is set too low. It has been reset to the rate specified in the message. Update
audio1575.conf to a higher record interrupt rate.
init_state() record interrupt rate set too high.
The record interrupt rate specified in audio1575.conf is set too high. It has been reset to the rate specified in the message. Update
audio1575.conf to a lower record interrupt rate.
SunOS 5.11 4 Nov 2005 audio1575(7D)