Hp 7475 Plotter Servo's

Has anybody had any experience with HP's 7475 Plotter servo's. I have an old hp 7475 plotter that seems to work (demo prints) but has a communication problem with my computer. Was wondering if any one has used these servo's in other projects? I.E. hooked them up to a servo controller and ran them off of another program such as EMC or one of the others? If I can't get the plotter to talk to the computer I would like to salvage the servo's and use as something else. The plotter has a constant blinking error light that will not reset, and does not seem to be communicating with the computer. I hooked up a new serial null modem cable, but still am unable to get the plotter to respond to the computer commands through DOS and the COM1 port.

I was thinking of maybe using the servo's in an egg decorating machine. I saw one on a CNC art web site.

I know the servo's work because from the control panel I can make the plotter pick up pens and also do the demo plot.

Any Suggestions?

Victor

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