Not much direct help from here, but my wife uses a...
product ([link|http://www.pcquilter.com/|a robotic quilting platform for a sewing machine]) which is controlled by a bi-directional parallel port and runs on XP as well as earlier flavors of Windows. The product, including all the hardware and related software is about $1100. So, obviously these folks found a way.
The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt. -- Bertrand Russell
They are not doing direct access.
They are doing "pseudo-direct access" or with a driver built for the purpose.
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