April 14, 2007 MAVB 4 sgimips

### NAME

mavb - Moosehead A/V Board audio device

### SYNOPSIS

mavb0 at mace0 offset 0x300000 intr 6 audio* at audiobus?

### DESCRIPTION

The mavb driver provides support for the Moosehead A/V Board found on SGI O2 machines.

The Moosehead A/V Board uses an AD1843 codec that supports 8- and 16-bit audio sample recording and playback at rates from 5 to 54 kHz, with 1 Hz resolution. The mavb driver also makes it possible to control the playback volume by using the buttons on the front of the O2.

### SEE ALSO

audio(4), intro(4), mace(4)

### HISTORY

The mavb driver first appeared in OpenBSD3.7. It was later ported to NetBSD5.0.

### AUTHORS

The mavb driver was written by Mark Kettenis, and ported to NetBSD by Jared D. McNeill.

### CAVEATS

The analog mixer in the AD1843 codec does not provide a master volume control. Therefore, the O2 volume buttons only control the output volume of the DAC.

### BUGS

Currently only sample rates up to 48 kHz are supported. Recording is not implemented yet. The second DAC on the AD1843 codec sits idle.