Computers, Software Engineering, and Digital Devices

Richard C. Dorf

• Publisher: CRC Press
• Year: 2018
• ISBN:
  9781351836548
• Edition: 1
• Topic: Informatique
• Subtopic: Ingénierie de l'informatique

In two editions spanning more than a decade, The Electrical Engineering Handbook stands as the definitive reference to the multidisciplinary field of electrical engineering. Our knowledge continues to grow, and so does the Handbook. For the third edition, it has expanded into a set of six books carefully focused on a specialized area or field of study. Each book represents a concise yet definitive collection of key concepts, models, and equations in its respective domain, thoughtfully gathered for convenient access.Computers, Software Engineering, and Digital Devices examines digital and logical devices, displays, testing, software, and computers, presenting the fundamental concepts needed to ensure a thorough understanding of each field. It treats the emerging fields of programmable logic, hardware description languages, and parallel computing in detail. Each article includes defining terms, references, and sources of further information.Encompassing the work of the world's foremost experts in their respective specialties, Computers, Software Engineering, and Digital Devices features the latest developments, the broadest scope of coverage, and new material on secure electronic commerce and parallel computing.

II

Computer Engineering

8 Organization R.F.Tinder, S.N. Yanushkevich, C. Hamacher, Z.Vranesic, S. Zaky, J.Raymond

Number Systems • Computer Arithmetic • Architecture • Microprogramming

9 Programming J.M. Feldman, E.W.Czeck, T.G. Lewis, J.J. Martin, M.D. Ciletti

Assembly Language • High-Level Languages • Data Types and Data Structures • The UseofHardware Description Languages in Computer Design

10 Input and Output S. Sherr

Input Devices

11 Secure Electronic Commerce M.H. Sherif

12 Software Engineering C.A. Argila, P.C. Jorgensen

Tools and Techniques • Software Testing

13 Computer Graphics N.C. Schaller, E.P Rozanski

Introduction • Graphics Hardware • Graphics Software • Graphics Algorithms • The Future

14 Computer Networks M.N.O.Sadiku, C.M. Akujuobi

OSI ReferenceModel • Local AreaNetworks • Metropolitan AreaNetworks • Wide Area Networks • ISDN and ATMNetworks • Internet

15 Fault Tolerance B.W. Johnson

Introduction • Hardware Redundancy • Information Redundancy • Time Redundancy • Software Redundancy • Dependability Evaluation

16 Knowledge Engineering M. Abdelguerfi, R. Eskicioglu, J. Liebowitz

Databases • Rule-Based ExpertSystems

17 Parallel Processors T.-y Feng, M. Kraetzl, Y.C. Lee, A.Y. Zomaya

Parallel Processors • Parallel Computing

18 Operating Systems R. Finkel

Introduction • Historical Perspective • Goals of an Operating System • Implementing an Operating System • Research Issues and Summary

19 Computer and Communications Security f.A. Cooper, A.M. Johnston

Introduction • Physical Security • Cryptology • Software Security • Hardware Security • Network Security • Personnel Security

20 Computer Reliability C.G. Guy

Introduction • Definitions of Failure, Fault, and Error • Failure Rate and Reliability • Relationship between Reliabilityand Failure Rate • Mean Time to Failure • Mean Time to Repair • Mean Time between Failures • Availability • Calculation of Computer System Reliability • Markov Modeling • Software Reliability • ReliabilityCalculations for Real Systems

8

Organization

Richard F. Tinder

Washington State University

S.N. Yanushkevich

University of Calgary

Carl Hamacher

Queen’s University

Zvonko Vranesic

University of Toronto

Safwat Zaky

University of Toronto

Jacques Raymond

University of Ottawa

Richard F. Tinder

8.1 Number Systems

Positional and Polynomial Representations • Unsigned Binary Number System • Unsigned Binary-Coded Decimal, Hexadecimal, and Octal Systems • Conversion between Number Systems • Signed Binary Numbers • Floating-Point Number Systems

8.2 Computer Arithmetic

Basics of Computing Arithmetic • Binary Adders • Multipliers • Arithmetic-Logic Units • Other Number Representations • Low Power Computing Arithmetic • Stochastic Arithmetic • Threshold Logic for Massively Parallel Systems • Computing Arithmetic of Nanostructures

8.3 Architecture

Functional Units • Basic Operational Concepts • Performance • Multiprocessors

8.4 Microprogramming

Levels of Programming • Microinstruction Structure • Microprogram Development • Emulation • Other Applications of Microprogramming

8.1 NUMBER SYSTEMS

Richard F. Tinder

Number systems provide the basis for conveying and quantifying information. Weather data, stocks, pagination of books, weights and measures—these are just a few examples of the use of numbers that affect our daily lives. For this purpose we find the decimal (or arabic) number system to be reliable and easy to use. This system evolved presumably because early humans were equipped with a crude type of calculator, their ten fingers. A number system that is appropriate for humans, however, may be intractable for use by a machine such as a computer. Likewise, a number system appropriate for a machine may not be suitable for human use.

Before concentrating on those number systems that are useful in computers, it will be helpful to review the characteristics that are desirable in any number system. There are four important characteristics in all:

• Distinguishability of symbols

• Arithmetic operations capability

• Error control capability

• Tractability and speed

To one degree or another the decimal system of numbers satisfies these characteristics for hard-copy transfer of information between humans. Roman numerals and binary are examples of number systems that do not satisfy all four characteristics for human use. On the other hand, the binary number system is preferable for use in digital computers. The reason is simply put: current digital electronic machines recognize only two identifiable states physically represented by a high voltage level and a low voltage level. These two physical states are logically interpreted as the binary symbols 1 and 0.

A fifth desirable characteristic of a number system to be used in a computer should be that it have a minimum number of easily identifiable states. The binary number system satisfies this condition. However, the digital computer must still interface with humankind. This is done by converting the binary data to a decimal and character-based form that can be readily understood by humans. A minimum number of identifiable characters (say 1 and 0, or true and false) is not practical or desirable for direct human use. If this is difficult to understand, imagine trying to complete a tax form in binary or in any number system other than decimal. On the other hand, use of a computer for this purpose would not only be practical but, in many cases, highly desirable.

Positional and Polynomial Representations

The positional form of a number is a set of side-by-side (juxtaposed) digits given generally in fixed-point form as

$Nr=\left(\underset{\text{Interger}}{\underbracket{{\stackrel{\stackrel{\text{MSD}}{\downarrow }}{a}}_{n-1}\cdots a_3{a}_2{a}_1{a}_0}}\stackrel{\stackrel{\text{Radix}\text{Point}}{\downarrow }}{\cdot }\underset{\text{Fraction}}{\underbracket{a_{-1}{a}_{-2}{a}_{-3}\cdots {\stackrel{\stackrel{\text{LSD}}{\downarrow }}{a}}_{-m}}}\right)r$

(8.1)

where the radix (or base) r is the total number of digits in the number system and a is a digit in the set defined for radix r. Here, the radix point separates n integer digits on the left from m fraction digits on the right. Notice that a_n−1 is the most significant (highest-order) digit, called MSD, and that a_-m is the least significant (lowest-order) digit, denoted by LSD.

The value of the number in Equation (8.1) is given in polynomial form by

$\begin{array}{l}Nr={\displaystyle \sum }_{i=-m}^{n-1}{a}_i{r}^i\hfill \\ ={\left(\begin{array}{l}{a}_{n-1}{r}^{n-1}+...+a_2{r}^2+a_1{r}^1+a_0{r}^0\hfill \\ +a_{-1}{r}^{-1}+a_{-2}{r}^{-2}+...+a_{-m}{r}^{-m}\hfill \end{array}\right)}_r\hfill \end{array}$

(8.2)

where a_i is the digit in the ith position with a weight rⁱ.

Application of Equation (8.1) and Equation (8.2) follows directly. For the decimal system r = 10, indicating that there are 10 distinguishable characters recognized as decimal numerals 0,1,2,…,r − 1 (= 9). Examples of the positional and polynomial representations for the decimal system are

$\begin{array}{l}{N}_{10}={\left(d_3{d}_2{d}_1{d}_0.d_{-1}{d}_{-2}{d}_{-3}\right)}_{10}\\ =3017.528\end{array}$

and

$\begin{array}{l}{N}_{10}={\displaystyle \sum _{i=-3}^{n-1}{d}_i{10}^i}\\ =3\times {10}^3+0\times {10}^2+1\times {10}^1+7\times {10}^0+5\times {10}^{-1}+2\times {10}^{-2}+8\times {10}^{-3}\\ =3000+10+7+0.5+0.02+0.008\end{array}$

where d_i is the decimal digit in the ith position. Exclusive of possible leading and trailing zeros, the MSD and LSD for this number are 3 and 8, respectively. This number could have been written in a form such as N₁₀ = 03017.52800 without altering its value but impl...