sac90286@uxa.cso.uiuc.edu (09/15/89)
I'm looking for plans, schematics, or any other information which would enable me to build an IBM PC compatible light pen. I have a CGA card with the standard IBM light pen port; all I need is the pen itself. As I understand it, the only working parts required are a photodiode/phototransistor and a microswitch, both small enough to mount inside a ball-point pen body. The light pen interface has a +5V and a +12V connection, a light pen input, a pen switch input, and (of course) a ground. Have I missed anything? How would I need to wire these parts together? Any and all assistance appreciated! Scott kubla@uiuc.edu