HARMONY(4) | Device Drivers 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 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 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 recorded.

May 31, 2007 | Debian