Owner`s manual

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Appendix D: WDM-Windows Driver Model FAQ
Q: What is a WDM driver and why should I care?
WDM stands for “Windows Driver Model.” Microsoft realized they were asking
hardware manufacturers to write a lot of different drivers: support for Windows
NT, Windows 95, support for the wave API, support for DirectSound, etc. To
encourage good driver development, they came up with the idea of WDM : you
can just write one driver that can run on all the different Windows platforms that
support all the different audio APIs.
You should care about WDM and our hardware if you meet any of the following
criteria:
-You are running Windows 2000 or Windows XP.
-You are running SONAR or some other audio application that talks directly
to WDM drivers.
If you are running Windows 95, 98, 98SE, or Me and are using the VxD drivers,
there probably isn’t a compelling reason to switch to WDM (unless you really,
really like the new console, or unless you have an audio application that takes
advantage of WDM).
Q: How is this driver different from the previously released
Windows 2000 beta drivers?
The previously released Windows 2000 beta drivers were actually Windows NT 4
drivers that could also be run under Windows 2000. They were not plug-n-play
(since NT 4 does not support plug-n-play), and they worked the “old way.”
What’s the old way? Here’s a simplified diagram:
Audio application
⇓
Echo wave driver
⇓
Echo kernel mode driver
⇓
PCI card
So, you can see the audio application would communicate more or less directly
with our wave driver (it doesn’t really, but that’s close enough for this
discussion). If an application wanted to use a specialized 24-bit format, we could
see what it was asking for and add support for that. This also let us control exactly
which wave devices were listed and how their names were listed.