The design of the control unit of an electronic digital computer
ABSTRACT The function of the control unit of an electronic digital computer is to provide the sequences of pulses, which, when applied to the store, arithmetic unit and other units of the machine, cause the orders of the programme to be executed. The paper discusses a number of related ways in which a systematic and flexible design for a control unit may be achieved. In one group of systems the order code is determined by the arrangement of diodes in a diode matrix, and in another by the appropriate threading of wires through a matrix of ferrite cores. The first part of the paper is concerned with logical design, and the second part with the practical design of a system using a ferrite matrix.
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ABSTRACT: A substantial part of the intellectual content of what H A Simon called the ‘sciences of the artificial’ is contained in the activity we calldesign. A central aim ofdesign theory is to construct testable, explanatory models of the design process that will serve to enhance our understanding of how artifacts are, or can be, designed. In this paper, we discuss how some of the basic concepts underlying the discipline ofartificial intelligence (ai) can serve to provide anexplanatory paradigm for understanding design. We present an AI-based model of the design process and describe some of the implications of this model for our understanding of design — including that aspect of it we call ‘invention’.Sadhana 02/1994; 19(1):5-21. · 0.59 Impact Factor
Article: Serial Matrix Storage Systems[Show abstract] [Hide abstract]
ABSTRACT: Coincident-current techniques, usually associated with parallel ferrite-core stores, may also be used for the operation of serio-parallel or purely serial memories. After outlining, in block diagram form, one possible physical realization of a serial system, the paper examines the conditions under which such a store is economically justified. The distinguishing feature of the system discussed is that coincidence is established in the memory matrix between two currents representing an address signal and a time signal, respectively. Studies of the characteristics and economics of serio-parallel devices are however not reported in detail. It is shown how the properties of the time-controlled serial store may lead to the adoption of a word-asynchronous design for serial digital computers. In such a machine, timing is not controlled or determined by limited store access. As examples, the paper indicates how the serial techniques facilitate the incorporation into small serial computers, of autonomous transfers, automatic floating point operations, high speed multiplication, division and shift orders and asynchronous transfers between, say, a high speed store and a magnetic drum.Electronic Computers, IRE Transactions on. 07/1961;
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ABSTRACT: This paper presents the design of a parallel digital computer utilizing a 20-Â¿sec core memory and a diode storage microprogram unit. The machine is intended as an on-line controller and is organized for ease of maintenance. A word length of 19 bits provides 31 orders referring to memory locations. Fourteen bits are used for addressing, 12 for base address, one for index control, and one for indirect addressing. A 32nd order permits the address bits to be decoded to generate special functions which require no address. The logic of the machine is resistor-transistor; the arithmetic unit is a bus structure which permits many variants of order structure. In order to make logical decisions, a ``general-purpose'' logic unit has been incorporated so that the microcoder has as much freedom in this area as in the arithmetic unit.Electronic Computers, IRE Transactions on. 07/1960;