1 .\" $NetBSD: guspnp.4,v 1.15 2008/04/30 13:10:54 martin Exp $
3 .\" Copyright (c) 1999 The NetBSD Foundation, Inc.
4 .\" All rights reserved.
6 .\" This code is derived from software contributed to The NetBSD Foundation
9 .\" Redistribution and use in source and binary forms, with or without
10 .\" modification, are permitted provided that the following conditions
12 .\" 1. Redistributions of source code must retain the above copyright
13 .\" notice, this list of conditions and the following disclaimer.
14 .\" 2. Redistributions in binary form must reproduce the above copyright
15 .\" notice, this list of conditions and the following disclaimer in the
16 .\" documentation and/or other materials provided with the distribution.
18 .\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19 .\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20 .\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21 .\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22 .\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 .\" POSSIBILITY OF SUCH DAMAGE.
35 .Nd Am78C201 audio device driver
37 .Cd "guspnp* at isapnp?"
38 .Cd "audio* at audiobus?"
40 There should be no limit caused by the driver on the number of drivers
41 or cards active in the system.
45 driver provides support for audio subsystems using the Interwave (Am78C20x)
46 family of ICs, usually the Gravis Ultrasound Plug and Play.
49 driver guspnp driver does not require any local memory for the IC, but uses
50 the codec for both playback and recording.
53 driver can simultaneously playback and record 8- and 16-bit samples at
54 frequencies from 5.51kHz to 48kHz.
60 to allocate suitable resources for it.
61 This version of the driver only
62 uses the first logical device of the five the Interwave IC has.
64 logical devices are the ATAPI CD-ROM device, PnP Joystick device, legacy
65 soundcard emulation device (SoundBlaster) and MIDI serial device.
67 for at least ATAPI CD-ROM and Joystick is being worked on.
68 This version of the driver will use 1 IRQ and 2 DRQs.
70 Cards supported by the
74 .Bl -item -offset indent
77 Ultrasound PNP, and compatibles
84 Interwave(tm) IC Am78C201/202 Programmer's Guide Rev. 2. 1996. Advanced
92 .An Kari Mettinen Aq Kari.Mettinen@helsinki.fi ,
93 University of Helsinki.
95 Sometimes you can cause a hiss on either left or right channel, or both.
96 You can usually make it disappear by playing random data, however this
97 might not be a very nice thing to your audio equipment, but it is the only
98 way I have found out to be effective.
100 Only the Codec is used in this version of the driver, therefore only 2
101 channels are supported (left and right). Also sound quality is probably
102 worse at lower kHz compared to playing through the synthesizer which does
105 If the implementation has a 'bad' oscillator, using frequencies 44.8kHz
106 and 38.4kHz will result in incorrect playback frequency. The author has
107 a GUS PnP Pro which displays this behavior.
109 Other members of the Interwave family have not been tested and don't
110 have the glue needed to make them work. Should someone need to implement it,
111 not many changes in the existing code are needed.
112 Output voltage control in
113 register CFIG2 [7] should be set differently for some other members of the
116 Other architectures than i386 haven't been tested. The bus_space abstraction
117 has been used from the beginning, so it should work.