1.\" $OpenBSD: harmony.4,v 1.9 2007/05/31 19:19:54 jmc Exp $ 2.\" 3.\" 4.\" Copyright (c) 2003 Jason L. Wright (jason@thought.net) 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 19.\" DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 20.\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 21.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 24.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 25.\" ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26.\" POSSIBILITY OF SUCH DAMAGE. 27.\" 28.Dd $Mdocdate: May 31 2007 $ 29.Dt HARMONY 4 hppa 30.Os 31.Sh NAME 32.Nm harmony 33.Nd CS4215/AD1849 audio device 34.Sh SYNOPSIS 35.Cd "harmony* at gsc? irq 13" 36.Cd "audio* at harmony?" 37.Sh DESCRIPTION 38The 39.Nm 40device uses the 41.Tn Crystal Semiconductor 42.Tn CS4215 4316-Bit Multimedia Audio Codec 44or 45.Tn Analog Devices 46.Tn AD1849 47.Tn SoundPort(R) Stereo Codec 48chip to implement the audio device interface described in 49.Xr audio 4 . 50This device is found on most 51.Tn HP PA-RISC 52workstations. 53The 54.Nm 55has a maximum precision of 16 bits and has a stereo input and stereo output. 56.Pp 57On 58.Tn HP 9000/712 59models 60.Nm 61also provides two additional channels for an add-on 62card with two fax/voice modems. 63.Pp 64One of the hardware registers reflects the state of the 65.Tn CHI 66bus that is used to communicate with the codec and thus 67being sampled at a low accuracy secondary frequency 68(such as 69.Xr timeout 9 ) 70produces poor quality random bit stream that is fed into the 71entropy pool of 72.Xr random 4 . 73.Sh SEE ALSO 74.Xr ioctl 2 , 75.Xr audio 4 , 76.Xr gsc 4 , 77.Xr intro 4 , 78.Xr random 4 79.Sh HISTORY 80.Ox 81support for 82.Nm 83first appeared in 84.Ox 3.3 . 85.Sh CAVEATS 86To trigger entropy collection 87.Tn CHI 88bus has to be programmed into the data mode that happens once 89a single buffer of data has been played or recorded. 90