Subject: k8v auvia and 20-bit audio
To: None <port-amd64@netbsd.org>
From: Wolfgang S. Rupprecht <wolfgang+gnus20040422T123432@dailyplanet.dontspam.wsrcc.com>
List: port-amd64
Date: 04/22/2004 12:50:30
I notice that the Asus k8v series literature talks about 20-bit audio
on their card.  I had assumed that means that one could actually play
20-bit audio with the right magic.

The auvia driver only knows about 8-bit and 16-bit right now.  The
documentation for the Analog Devices AD1980 codec is readily available
and switching it to 20-bit mode is trivial.  The rub seems to be that
one also needs to switch the VIA VT8237 south-bridge controller to
fetch the 20 bits from main memory somehow.  I spent some time
yesterday looking for documentation on the VT8237 but came up totally
empty handed.  Does anyone here have access to the VIA documentation?
Is it even possible to configure this chip to fetch either 24-bit or
32-bit audio samples and load 20 of those bits into the codec?

-wolfgang
-- 
Wolfgang S. Rupprecht 		     http://www.wsrcc.com/wolfgang/