Table Of ContentTheory and Design of
Digital Computer
Systems
Second edition
Douglas Lewin
Formerly Profe~sor of Digital Processes
Bronel University
and
David Noaks
CEE Technology Management
Warwickshire
SPRINGER-SCIENCE+BUSINESS MEDIA, B.V.
First published in 1972 as Theory and Design of Digital Computers
New edition published in 1980 as Theory and Design of Digital Computer
Systems
Reprinted 1981
Second edition 1992
tel 1972, 1980 Douglas Lewin; 1992 The Estate of Douglas Lewin and
I>avid Noaks
Originally published by Kluwer Academic Publishers in 1992
Typeset in 10/12 pt Times by Excel Typesetters Company, Hong Kong
ISBN 978-0-412-42880-7 ISBN 978-94-011-1576-6 (eBook)
DOI 10.1007/978-94-011-1576-6
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A catalogue record for this book is available from the British Library
Library of Congress Cataloging-in-Publication data
Lewin, Douglas.
Theory and design of digital computer systemslDouglas Lewin,
David Noaks. - 3rd ed.
p. cm.
Includes index.
ISBN 978-0-412-42880-7
1. Electronic digital computers - Design and construction.
I. Noaks, David. 11. Title.
TK7888.3.L38 1992
004 - dc20 92-30621
CIP
Printed on permanent acid-free text paper, manufactured in
accordance with the proposed ANSIINISO Z 39.48-199X-and
ANSI Z 39.48-1984
Contents'
Preface xi
1 The stored program principle 1
1.1 Introduction 1
1.2 Instruction and number representation 4
1.3 Computer operation 11
1.4 Applications 13
References and bibliography 15
2 Data representation and computer arithmetic 16
2.1 Data types 16
2.2 Binary codes 17
2.3 Error detection 21
2.4 Error-correcting codes 23
2.5 Negative numbers 24
2.6 Binary arithmetic 25
2.7 Floating-point numbers 28
References and bibliography 30
Tutorial problems 31
3 Computer organization and programming 32
3.1 Instruction set and operation codes 32
3.2 Instruction formats 33
3.3 Organization of data and instructions in memory 37
3.4 Addressing modes 38
3.5 Machine-Iangu~.ge programming 43
3.6 Subroutines 56
3.7 Stacks and re-entrant code 57
3.8 Expansion of storage capacity 62
3.9 Assembly-language programming 63
3.10 Procedure-orientated languages 67
3.11 Register transfer languages 68
3.12 Processor structure 71
I I
vi CONTENTS
3.13 Instruction execution 74
References and bibliography 74
Tutorial problems 76
4 Control structures and microprogramming 78
4.1 Control unit organization 78
4.2 Logic components 81
4.3 The microprogram concept 99
4.4 Microinstruction formats 107
4.5 Microprogrammable structures 111
4.6 Programming the microprogram control unit 119
References and bibliography 121
Tutorial problems 123
5 Arithmetic algorithms and processors 125
5.-1 Introduction 125
5.2 Binary addition and subtraction circuits 126
5.3 Serial full-adder circuits 131
5.4 Cascaded serial adder circuits 134
5.5 Parallel full-adder circuits 138
5.6 Carry-completion adder circuit 139
5.7 Carry look-ahead adder circuits 142
5.8 Carry-save adders 148
5.9 Overflow and out-of-range circuits 149
5.10 Binary-coded decimal adders 151
5.11 Unsigned binary multiplication 153
5.12 Array multiplication 157
5.13 Fast multiplier circuits 163
5.14 Binary division circuits 170
5.15 Multiplication and division of signed binary numbers 174
5.16 Round-off of binary numbers 178
5.17 Floating-point binary arithmetic 180
5.18 Software implementation 185
5.19 Error-detecting arithmetic logic 185
References and bibliography 193
Tutorial problems 194
6 Memory systems 196
6.1 Introduction 196
6.2 Characteristics of memory devices 197
6.3 Memory hierarchy 199
6.4 Semiconductor memories 201
6.5 Magnetic recording and storage techniques 218
6.6 Optical disk storage 235
I I
CONTENTS vii
6.7 Associative memory 236
6.8 Cache memory 237
6.9 Virtual memory 242
6.10 Memory-management systems 244
References and bibliography 249
Tutorial problems 251
7 Input/output systems 252
7.1 Introduction 252
7.2 The input/output function 255
7.3 Peripheral devices 256
7.4 Input/output interfaces and buses 264
7.5 Interrupt mechanisms 271
7.6 Direct memory access 275
7.7 Communications interfaces 277
7.8 Input/output processors 280
7.9 Graphics systems 283
References and bibliography 285
Tutorial problems 286
8 Advanced computer architectures 288
8.1 Introduction 288
8.2 Parallel processing 289
8.3 Digital signal processors (DSPs) 326
8.4 Reduced instruction set computers (RISC) 334
8.5 Associative processors 338
8.6 Languages 343
References and bibliography 346
9 Computer networks 349
9.1 Introduction 349
9.2 Data transmission 351
9.3 Protocols 354
9.4 Local area networks (LANs) 360
9.5 Wide area networks (WANs) 370
References and bibliography 372
Tutorial problems 373
10 Engineering and system aspects 375
10.1 Introduction 375
10.2 Realizing the logic design 378
10.3 Noise problems 388
10.4 System testing procedures 395
10.5 Logic testing and simulation 399
J
~] [--- ___C_ O_N_TENTS _________________
10.6 Reliability and the use of redundancy 407
10.7 Software tools 419
References and bibliography 426
Tutorial problems 429
Worked solutions to selected problems 431
Appendix 1 Logic symbols 467
Al Introduction 467
A2 Symbol structure 467
A3 Dependency 470
A4 MIL-STD-806B logic symb~ls 474
Appendix 2 Glossary of abbreviations 475
Index 479
Preface
Knowledge: A little light expels much darkness _
Bahya ibn Paquda, Duties of the Heart
During the early 1970s digital computer techniques concentrated on the
computational and interfacing aspects of digital systems and the decade
began as the age of both the mainframe computer and the minicomputer.
Engineers and system designers needed to know the fundamentals of
computer operation and how the practical limitations of the architectures
of the day, the memory size, cost and performance could be overcome; it
was for this reason that this book was first written.
By 1980 the microprocessor revolution had arrived. As a result the
microprocessor became a component of a system, rather than a system
itself, and the need to understand the behaviour of the device became of
even greater importance to the system designer. New developments in
mainframe computers were few, with networks of minicomputers taking
over their role in many instarices. The 1980 revision of this book took
into account the major advances in semiconductor technology that had
occurred since it was first published in 1972, and included material
relevant to the microprocessor.
Perhaps one of the most significant advances in the use of digital
techniques in the 1980s was in digital communications and the use of
computer networks and public networking for the transmission of digital
data. The requirement to understand basic digital system principles in
order to develop these systems remains unchanged, as indeed have the
computer principles themselves, although greater freedom is available to
design more complex computer architectures.
The second edition of this book is a complete revision of all chapters
of the 1980 edition, updating the material with respect to current practical
semiconductor processes and magnetic materials in general use, and
adding additional material on digital signal processors and a completely
new chapter on computer networks.
The outline of this revision was undertaken by Douglas Lewin before
_________________
~_x~1 I~ PR_E_F_A_C_E_ _______________~
his untimely death. It has been my privilege, as both a friend and a
colleague for many years and one of many who have used his texts for
teaching in university and polytechnic engineering courses, to have been
asked by Gerry Musgrave on behalf of Douglas's daughter Terina to
complete the revision.
David R. Noaks
Si quid novisti rectius istis,
Candidus imperti; si non, his utere mecum
-. HORACE
'Now, brother, if a better system's thine,
Impart it frankly, or make use of mine.'
The stored program
1
principle
1.1 INTRODUCTION
There are two basic types of computer - the analogue computer and the
digital computer - together with a combination of the two called the
hybrid computer. The technology of the time dictated that the analogue
computer predated the digital, and its application was almost entirely in
engineering rather than in commerce. Nowadays the situation is reversed
and the digital computer, which has a very much broader field of applica
tion, predominates. In this book we shall be concerned 'primarily with the
digital computer, but before we start it is worth describing the charac
teristics of all three types.
The analogue computer represents the variaBles (and constants) in its
calculations by physical quantities (usually voltage and time): hence the
name 'analogue'. The slide rule is a very simple example, where length is
used to represent the actual values in a calculation. The accuracy of
such calculations is of course limited by the accuracy with which we
can measure the physical quantities involved. Usually the computing
reference voltage is ± 10 V, and voltmeters, oscilloscopes and X -Y
plotters are used to measure and record the values of the variables,
generally to within an accuracy of 0.1-1 %.
The solution to a mathematical or systems problem is obtained by
setting up an analogue of the mathematical equations (or by simulating
its transfer functions) using operational amplifier circuits functioning
as adders, sign changers, integrators, and so on [1]. Thus each integra
tion or addition, etc., in an equation is performed simultaneously by
separate operational amplifiers working in parallel. Consequently the
answer is in a continuous form; that is, the analogue computer produces a
gene~al solution to an equation which is normally displayed as a graph
