Subject: Re: Audio support
To: Chris Gilbert <cg110@york.ac.uk>
From: Ale Terlevich <A.I.Terlevich@durham.ac.uk>
List: port-arm32
Date: 02/18/1997 18:34:34
On Tue, 18 Feb 1997, Chris Gilbert wrote:

> 
> On Thu, 13 Feb 1997, Peter Berg wrote:
> 
> > Hi,
> > 
> > can someone tell me the current state of the 16bit audio device for RiscBSD ?
> 
> I have seen in the kernel source dir a driver called lmcaudio (or

  Dunno what that is.

  There's a vidcaudo driver already in the kernel.

If you create the /dev/audio device, then sending something to that 
creates a bit of noise on the speaker and then hangs the process writing 
to /dev/audio for a bit.

  However if you have a kernel without the beep device, you get no beep 
in X, but you can send stuff to /dev/audio.

  I seem to remember you have to send it raw 16bit data and ata weird 
sample rate. It also seems unable to keep the visc20's input fifo full 
and keeps clicking regularly. Soud quality's hardly recognisable too :)

  If you up the sample rate (I recompiled the kernel, but I assube you 
could just use an ioctl) then you get a decent sample rate, but LOADS of 
clicks per second. (I think the input buffer can't be > page size = 4k).

  Having looked at the source, most of it's missing, so it's harly 
surprising that it doesn't work :)

Ale.