Subject: Re: PCMCIA sound card, yet again...
To: Jared D. McNeill <jmcneill@invisible.yi.org>
From: Jason R Thorpe <thorpej@zembu.com>
List: current-users
Date: 01/04/2001 13:39:10
On Thu, Jan 04, 2001 at 05:25:07PM -0400, Jared D. McNeill wrote:
> 4) DMA EMULATION
> The Eiger Labs PC Stereo Sound Card version 2.2 provides DMA Emulation.
> DMA Emulation supports Sound Blaster Compatibility for Windows 95 and
> DOS sessions running under Windows 95. Configuration for DOS only
> requirements is still under research. In this situation, the challenge
> is providing DMA support through the PCMCIA socket. PCMCIA 2.1 specifications
> DO NOT support DMA. Consequently, reliable execution of games and other
> programs which have high demands on precise hardware DMA operations cannot
> always be provided.
>
> DMA Emulation for DOS/Windows 3.X is not currently available.
Right, so sounds like the driver for the card "emulates" DMA somehow,
and is really doing programmed I/O.
This is what you'll have to do. I suggest you get the docs for the ESS 1688.
You might be able to glue it into the existing ess driver, or you might have
to start from scratch.
--
-- Jason R. Thorpe <thorpej@zembu.com>