HARMONY(4)            OpenBSD Programmer's Manual (HPPA)            HARMONY(4)

NAME
     harmony - CS4215/AD1849 audio device

SYNOPSIS
     harmony* at gsc? irq 13
     audio*  at harmony?

DESCRIPTION
     The harmony device uses the Crystal Semiconductor CS4215 16-Bit Multime-
     dia Audio Codec or Analog Devices AD1849 SoundPort(R) Stereo Codec chip
     to implement the audio device interface described in audio(4).  This de-
     vice is found on most HP PA-RISC workstations.  The harmony has a maximum
     precision of 16 bits and has a stereo input and stereo output.

     On HP 9000/712 models harmony also provides two additional channels for
     an add-on card with two fax/voice modems.

     One of the hardware registers reflects the state of the CHI bus that is
     used to communicate with the codec and thus being sampled at a low accu-
     racy secondary frequency (such as timeout(9)) produces poor quality ran-
     dom bit stream that is fed into the entropy pool of random(4).

SEE ALSO
     ioctl(2), audio(4), gsc(4), intro(4), random(4)

HISTORY
     OpenBSD support for harmony first appeared in OpenBSD 3.3.

CAVEATS
     To trigger entropy collection CHI bus has to be programmed into the data
     mode that happens once a single buffer of data has been played or record-
     ed.

OpenBSD 4.7                      May 31, 2007                                1
