Plotter Part 1

30 EE May 1988 Many owners of a personal computer and associated peripheral equipment will at some time have wished that graphics information available on screen could be sent to a plotter instead of a slow, noisy printer operated in the dot-matrix mode. But then, even the simplest of plotters is often more expensive than the computer itself. Not so the plotter described here, which is a unique project: fairly simple to build, complete with a versatile and power-efficient stepper motor interface driver, available in kit form, and offering a good price/performance ratio. The final accuracy of the plotter should be adequate for a host of graphics applications, and depends mainly on the constructor"s mechanical skills. Matrix printers are fine for text appli- cations, but can not handle graphics in- formation very well. They are invariably slow because in the bit image mode pix- els are printed one line at a time. In ad- dition, their resolution is insufficient for many applications,...