HARMONY(4) OpenBSD Programmer's Manual (HPPA) HARMONY(4)NAMEharmony - CS4215/AD1849 audio device
SYNOPSIS
harmony* at gsc? irq 13
audio* at harmony?
DESCRIPTION
The harmony device uses the Crystal Semiconductor CS4215 16-Bit
Multimedia Audio Codec or Analog Devices AD1849 SoundPort(R) Stereo Codec
chip to implement the audio device interface described in audio(4). This
device 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
accuracy secondary frequency (such as timeout(9)) produces poor quality
random bit stream that is fed into the entropy pool of random(4).
SEE ALSOioctl(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
recorded.
OpenBSD 4.9 May 31, 2007 OpenBSD 4.9