If you're working on windows check out the windows driver development kit. I don't know the link information, but it shouldn't be hard to find microsofts website.
OlyComputers
Practically a Master Poster
611 posts since Jun 2008
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There isn't, to my knowledge, such a thing as a driver for BIOS. Your BIOS either recognizes a component or it doesn't. If you need this as a tool for product start by making sure you have usb keyboards enabled in your bios, if you can't use a hardware USB to PS/2 adapter, but if the driver itself is the project it will be more complicated. Are you sure you're talking about DOS here? I'm pretty sure that Vistas command line is not DOS anymore.
Can you tell us the actual guidelines of the project so we know exactly what you're looking for.
OlyComputers
Practically a Master Poster
611 posts since Jun 2008
Reputation Points: 124
Solved Threads: 36