Programmable controller for controlling reproduction machines

Abstract

A programmable controller is utilized to control a reproduction machine for producing impressions of an original on a support material. The reproduction machine includes a photosensitive member and a plurality of discrete operating components mutually cooperable with the photoreceptive member to electrostatically produce the impressions. The programmable controller incorporates a computer which operates under the direction of a master program. The computer calculates timing signals in accordance with the program information and stores the timing signals in a memory for later actuation of the components in a properly timed sequence to produce the copies desired. The machine, under the direction of the computer, periodically checks the operability of at least one of the operating components in the interval between the timing signals. Similarly, the timing signals stored in the memory are periodically updated during the intervals between actuation of the operating components.