1.\" 2.\" Copyright (c) 1998, Luigi Rizzo 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd June 3, 1998 29.Dt PCM 4 30.Os FreeBSD 31.Sh NAME 32.Nm pcm 33.Nd FreeBSD PCM audio device driver 34.Sh SYNOPSIS 35For a card with bridge driver support, and a PnP card: 36.Cd "device pcm" 37.Pp 38For a card without bridge driver support, and a non-PnP card: 39.Cd "device pcm0 at isa? port? irq 5 drq 1 flags 0x15" 40.Sh DESCRIPTION 41The 42.Nm 43driver provides support for PCM audio play and capture. 44This driver 45also supports various PCI and WSS/MSS compatible ISA sound cards, and 46AC97 mixer. 47True full duplex operation is available on most cards. 48.Pp 49If your sound card is supported by a bridge driver, 50.Nm 51driver works 52in conjunction with the bridge driver. 53.Pp 54Apart from the usual parameters, the flags field is used to specify 55the secondary DMA channel (generally used for capture in full duplex 56cards). Flags are set to 0 for cards not using a secondary DMA 57channel, or to 0x10 + C to specify channel C. 58.Pp 59The driver works best with WSS/MSS cards, which have a very clean 60architecture and an orthogonal set of features. 61They also happen to be 62among the cheapest audio cards on the market. 63.Pp 64The driver does its best to recognize the installed harware and drive 65it correctly, so that you don't have to give too many details in the 66kernel config files. 67For PCI and ISA PnP cards this is actually easy 68since they identify themselves. 69For legacy ISA cards, the driver looks 70for MSS cards at addresses 0x530 and 0x604 (obviously, unless overridden 71in the kernel config file by specifying an address). 72 73.Sh IOCTL 74The driver supports most of the Voxware ioctls(), and most 75applications work unmodified (including popular mpeg players and linux 76binaries). A few 77differences exist (the most important one is the ability to use 78memory-mapped access to the audio buffers). As a consequence, some 79applications may need to be recompiled with a slightly modified 80audio module. See /usr/include/sys/soundcard.h for a complete 81list of the supported ioctls. 82 83.Sh SUPPORTED CARDS 84.Pp 85Below we include a list of supported codecs/cards. 86If your sound card 87is not listed here, it may be supported by a bridge driver. 88 89.Bl -tag -width 2m % begin list 90.It CS4237, CS4236, CS4232, CS4231 (ISA) 91.Pp 92All these cards work perfectly in full duplex using the MSS mode. 93This chipset is used, among others, on the A/Open AW35 and AW32, on 94some Intel motherboards, and (the CS4231) on some non-PnP cards. 95.Pp 96The CS4232 is reported as buggy in the Voxware documentation but 97I am not sure if this is true. 98On one of my Intel motherboards, 99capture does not work simply because the capture DMA channel is 100not wired to the ISA DMA controller. 101 102.It Yamaha OPL-SAx (ISA) 103.Pp 104Works perfectly in all modes. 105This chip is used in several PnP cards, 106but also (in non-PnP mode) on motherboards and laptops (e.g. the 107Toshiba Libretto). 108 109.It OPTi931 (ISA) 110.Pp 111The chip is buggy, but the driver has many workarounds to make it work 112in full duplex because for some time these were the only full duplex 113cards I could find. u-law formats uses U8 format internally because of 114a bug in the chip. 115 116.It Trident 4DWave DX/NX (PCI) 117.Pp 118.It ENSONIQ AudioPCI ES1370/1371 (PCI) 119.Pp 120Creative Labs SoundBlaster PCI is supported as well. 121 122.It NeoMagic 256AV/ZX (PCI) 123.Pp 124.El 125.Pp 126.Sh DIAGNOSTICS AND TROUBLESHOOTING 127.Bl -tag -width 2m 128.It ac97: dac not ready 129AC97 codec is not likely to be accompanied with the sound card. 130 131.It unsupported subdevice XX 132A device node is not created properly. 133 134.El 135.Sh BUGS 136Some features of your cards (e.g. global volume control) might not 137be supported on all devices. 138.Sh HISTORY 139The 140.Nm 141device driver first appeared in 142.Fx 2.2.6 , 143rewritten in 144.Fx 4.0 . 145.Sh SEE ALSO 146.Xr sbc 4 147.Xr gusc 4 148.Xr csa 4 149.Sh AUTHORS 150.An Luigi Rizzo Aq luigi@iet.unipi.it 151initially wrote the 152.Nm 153device driver and this manual page. 154.An Cameron Grant Aq gandalf@vilnya.demon.co.uk 155totally revised the device driver. 156.An Seigo Tanimura Aq tanimura@r.dl.itc.u-tokyo.ac.jp 157revised this manual page. 158