Small Digital Computers

Small Digital Computers 

(minicomputers), small digital computers with speeds of up to several thousand operations per second and a memory capacity of up to several thousand words. They are designed for simple computations, primarily for engineering calculations, processing the results of measurements, and compilation of production schedules at research institutes, design bureaus, planning organizations, educational institutions, and production associations and enterprises. At computer centers, small digital computers are used to prepare and order raw data and record it on punched cards or tape, magnetic tape, and other carriers. During preliminary processing of raw data they are used for computations on limited problems that do not require great speed, and also for converting the results of a general-purpose digital computer and providing communication between it and the user.

The main characteristics of small digital computers are a simple set of operations intended for processing with several positions, usually in the decimal system of notation; the use of an algorithmic language that is simplified as much as possible and approximated to the language of mathematical formulas, which accelerates the process of training laymen to work with the computer; input of information from a keyboard (for example, an electric typewriter) or from punched tape, and graphic output of results on paper, digital display tubes, and cathode-ray tubes; and an easy-to-use control console. Microprogramming control is used extensively.

Small digital computers usually include devices for control, direct-access and long-term memory, and data input-output (see Table 1). The software consists of a set of programs that are partially stored in long-term memory and make possible the solution of systems of algebraic and differential equations, the calculation of matrices and graphs, the processing of statistical data, and the performance of various bookkeeping and invoicing operations, as well as programs for processing and shaping data files and for the output of results in the form that is most convenient for the user.

A. V. GUSEV