Are you talking about driving real motors and such, or just modelling
them in software? If you want to connect to the outside world,
by far the simplest approach is to use the parallel printer
port on a Win9x machine. You get 8 (or more) output lines
to do with as you wish under software control. These can
drive relays or switching transistors that then drive motors
or whatever you want.
Th reason I said Win9x is that NT, XP, 2K, etc, don't
allow direct port control. However, you can get special
Ring 0 drivers that do allow this. (GIVEIO and USERPORT
are two that I've heard of, but never tried.)
Since you are probably new to port programming, you
might want to check out www.lvr.com
They have lots of info on all kinds of ports, but the
parallel is simplest to interface for this application.
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