Design of a Plotting System for a Remote Terminal of a Time-Shared Digital Computer

摘要

The need for plotting systems which will operate from data sent to the remote terminals of time-shared digital computers is discussed. From this discussion the specifications for a plotting system are formulated. The system proposed is one which will in no way affect the central computer except through programming. It is a low-cost system which will produce smooth plots and which will provide voltages for driving analog X-Y plotters, storage cathode-ray tubes, and other voltage-driven devices. A preliminary design of two systems which meet the specifications are discussed and compared. One of the designs, a digital-to-analog multiplexer system, is selected and an engineering prototype is described. Plots of various functions plotted by the prototype on an X-Y plotter and on a storage tube are shown. All test results indicate that the system accuracy is better than 1%. System performance and costs are discussed. A listing of the computer program which is used in conjunction with the plotting system is included. The plotting data prepared by this program for a parabola and for a sine wave are also shown. (Author)