February 1979 Volume 12 Number 2 (ISSN 0018.9162)

THEME FEATURES

Cover photo: Rick CobbCover design: Jay Simpson

9 Guest Editors' Introduction: 1978 Asilomar Workshop on

Microprocessors Bernard L. Peuto and Leonard J. Shustek10 Architecture of a New Microprocessor Bernard L. Peuto

Increased capabilities, architectural compatibility, and clearly defined interfaces were thechief architectural goals of Zilog's new Z8000 microprocessor family. Here is an account ofhow those goals were met for two members of that family-the Z8000 CPU and the MMU.

22 Intel MCS-48 Microcomputer Family: A Critique John F. WakerlyA system designer and teacher, who has made liberal use of microcomputers in his ownwork and whose students have designed 8048 processors, reviews the capabilities andlimitations of the MCS-48 family of microcomputers.

32 State Description Techniques Applied to IndustrialMachine Control Jack V. LandauA state language, useful for describing the control software for appliances and industrialmachines, has been used with a programmable industrial sewing machine, yielding benefitsmuch like those of structured programming.

MICROSYSTEMS 43 A Microprocessor Architecture for a Changing World:The Motorola 68000 Edward Stritter and Tom GunterThe first implementation of a new microprocessor architecture promises to narrow the gapbetween the power of very small and very large computers.

53 Macro-Assemblers and Macro-Based Languages in MicroprocessorSoftware Development Harvey A. Cohen and Rhys S. FrancisUsing a conventional macro-assembler as a multi-target cross-assembler and cross-compiler,the authors developed portable algorithmic code for microprocessor controllers.

SPECIAL FEATURES 66 An Introduction to Algorithm Design Jon Louis BentleyFast algorithms dramatically decrease run time for certain tasks. Designing them offersnot only the promise of better performance but also a better understanding of theproblems underlying all computational tasks.

79 Evolved Software for the 80's L. A. BeladyTo reach a better balance between free innovation and disciplined construction, we mustbring an experimental element to software engineering, creating a modifiable andconfigurable software inventory composed of reusable and verified program parts.

84 Workshop Report: Software Quality Assurance StandardsUnder Development Phil Rosengard

86 Workshop Report: Dedicated Microcomputers for Defenseand Industry Thomas H. Nyman and Paul Hazan

89 Open Channel: On Informatism C. K. Yuen

DEPARTMENTS 3 Special Message 103 Update: AFIPS Washington Report91 New Products 107 Calendar94 New Literature 108 Call for Papers95 IC Announcements 110 Book Reviews: High-Level-Language96 Microsystems Announcements Computer Architecture; An Introduction97 New Applications: Reading to Data Structures with Applications

Machine for the Blind 112 Advertisers/Product Index99 Repository 115 The Bookshelf

Coming Next Month: 100 Classified AdsData Base Machines Reader Service Cards and Order Forms, pp. 113-114.

1February 1979

Editor and Publisher:True SeabornIssue Editor: Marilyn Potes

Senior StaffEditor: M#rilyn PotesStaff Editor: J. B. SchallanConferences Editor: Christina TaylorContributing Editor: Ware MyersArt Director: Jay SimpsonProduction: Larry Bauer

Advertising Director: Dawn PeckAdvertising Production: Helen Bower

IEEE COMPUTER SOCIETYPresident: Tse-yun Fengi,i

First Vice-President-Technical Interest Council I-Software & Applications: E. A. Parrish2

Second Vice-President-Conferences & Meetings:M. C. Mulder2

Vice-President-Chapter Activities: C.V. Ramamoorthy2Vice-President-Publications: R. E. Merwin2

Vice-President--Technical Interest Council II-Systems Technology: N. R. Kornfield

Secretary: N. Garcia2Treasurer: M. E. Sloani

Junior Past President: M. G. Smith2IEEE Division VDirector: R. E. Merwin'

GOVERNING BOARD(Voting Members)

Term Ending Term EndingDecember 31,1979 December 31,1980G.I. Davida L.D. AmdahlP.H. :nslow K.R. AndersonK.S. Fu O.N. Garcia2J.D. Grimes E.D. JensenP.L. Hazan G. J. LipovskiR.E. Merwin2 S. MadnickC.V. Ramamoorthy2 R. RussoR. Rice M.E. SloanJ.N. Snyder H.S. StoneR.T. Yeh R.E. Theisen

SOCIETY REPRESENTATIVES

AFIPS Directors: T. Feng, M.G. Smith, S.S. YauAFIPS Executive Committee: M.G. SmithIEEE Liaison with Information Theory Group: R. MillerIEEE Publications Board: T. BonnIEEE Oceanic Engineering Council: D. Stomberg,G.N. Williams

IEEE Solid-State Circuits Counci- F.K. Buelow,R.A. Henle

Institute for Certification of Computer Professionals:J.N. Snyder, M. Prastein

National Computer Conference Board- D.B. SimmonsTAB Awards Committee: J. LogueTAB Conferences & Meetings Committee: D. Hartmann.'T. Feng Next board meeting:Dept. of Elec. & Computer Eng'g 3/2/79 Jack TarWayne State University Hotel,Detroit, MI 48202 San Francisco

2Executive Committee Member3Harry Hayman, P.O. Box 639Silver Spring, MD 20901

'Technical Editor: Portia IsaacsonAssociate Technical Editors: Dennis R.Allison (Microsystems), Oscar N. Garcia,James H. Haynes (Open Channel), Samir S. Husson,Ted G. Lewis, Francis P. Mathur (Book Reviews),Demitri A. Michalopoulos (New Products), EdwardF. Miller, Jr., Bruce D. Shriver

Computer Advisory BoardChairman: Rex RiceLowell D. Amdahl, Jack D. Grimes,Jack E. Shemer, Russell E. Theisen

Ex officio:Paul Hazan, Portia Isaacson, Richard E. Merwin,H. T. Nagle, Jr., True Seaborn

TAB Finance Committee: M. SloanTAB Membership Committee: S. HorvitzTAB Transnational Committee: H. FreitagUSAB-PAC Coordinator: L. Hopewell

SENIOR STAFF MEMBERSExecutive Secretary: H. Hayman3Publications Office: H. T. Seaborn

STANDING COMMITTEE CHAIRMENAdmissions and Advancement: E. A. ParrishAwards: R. RiceChapters: C. V. RamamoorthyChapter Activities Newsletter: L. MaxsonChapterDevelopment: R. E. TheisenDistinguished Visitor's Program:'E. ReingoldStudentActivities: 0. N. GarciaTutorial Program: D. Pessel

COMPCON Spring: S. FernbachCOMPCON Spring 79: D. Brown

COMPCONFalL D. HartmannCOMPCON Fall 79: P. Isaacson

COMPSAC: S. S. YauCOMPSAC 79: W. B. Smith

Computer Standards: R. G. StewartConferences and Meetings: M. C. MulderConstitution and Bylaws: R. E. TheisenConference Coordinator: G. J. Lipovski

Education: D. C. RineFellows: S. LevineFinance: M. E. SloanIntersociety: M. G. SmithMembership & Transfers: R. E. TheisenNominations: M. G. SmithPublications: R. E. MerwinComputer:Technical Editor: P. IsaacsonEditor and Publisher: H. T. Seaborn

Transactions on Computers: T. BoothTransactions on Software Engineering: R. T. YehTransactions on Pattern Analysis andMachine Intelligence: K. S. Fu

Ad hocComputing Careers: M. E. SloanLong Range Planning: M. G. SmithMember Brochure: D. PesselOperations: M. E. SloanProfessional Development: S. Winkler

TECHNICAL INTEREST COUNCILS

Technical Interest Council I-Software & ApplicationsChairman: E. A. ParrishVice-chairman: S. D. ShapiroSecretary: J. H. AylorChapter Affairs: B. Patz

Publications CommitteeChairman: Richard E. MerwinSidney Fernbach, S. R. Kimbleton, G. J. Lipovski,J. F. Meyer, C. V. Ramamoorthy,S. S. Reddy, Jack E. Shemer,J. N. Snyder, David Stomberg,Stanley Winkler

Ex officio:T. H. Bonn, Taylor Booth, K. S. Fu,Portia Isaacson, Rex Rice, True Seaborn,Raymond T. Yeh

Computer Advisory Board. H. T. Nagle, Jr.Education Affairs: G. EngelStandards Affairs: T. FengTutorial Affairs: D. IrwinPublications Affairs: D. StombergTechnical Committee Representatives: R. V. Book,Y. T. Chien, G. I. Davida, D. Fife,S. Madnick, J. F. Meyer, J. G. Peddie,N. Schneidewind, D. Stomberg

Technical Interest Council lI-Systems TechnologyChairman: N. R. KornfieldVice-chairman: W. V. VilkelisSecretary: A. K. GokselChapter Affairs: S. HorvitzComputer Advisory Board: P. L. HazanConference Affairs: W. D. CarrollEducation Affairs: T. AgerwalaPublications Affairs: S. WinklerStandards Affairs: L. KayeTutorial Affairs: W. LuciwTechnical Committee Representatives:K. R. Anderson, D. Atkins, A. D. Close, P. L. Hazan,P. Losleben, T. G. Rausher, K. J. Thurber,I. Tjomsland, P. Verhofstadt, C. Vick

TECHNICAL COMMITTEE CHAIRMENComputerArchitecture: D. AtkinsComputer Communications: K. J. ThurberComputerElements; P. VerhofstadtComputer Packaging: A. D. CloseData Acquisition & Controt- J. G. PeddieData Base Engineering: S. MadnickDesign Automation: P. LoslebenDistributed Processing: C. VickFault Tolerant Computing: J. F. MeyerMachine Intelligence & Pattern Analysis: Y. T. ChienMass Storage: I. TjomslandMathematical Foundations of Computing: R. V. BookMicroprogramming: T. G. RauscherMini/Micro Comptuers: P. L. HazanOceanic Engineering & Technology: D. StombergOperating Systems: H. L. ApfelbaumSecurity & Privacy: G. I. DavidaSimulation: N. F. SchneidewindSoftware Engineering: D. FifeTest Technology: K. K. Anderson

AREA COMMITTEE CHAIRMANNortheastern Area. R. MattesonMideastern Area: C. B. HensleySoutheastern Area: W. D. CarrollOhio Valley Area: R. HoelzemanMidwestern Area: A. S. WojcikSouthwestern Area: W. K. KingWestern Area: R. Nilsen

Conference Affairs: J. Shen Eastern Hemisphere & Latin America: R. C. Barquin

A. INSTITUTE OF ELECTRICAL Dvsoa ietrAND ELECTRONICS ENGINEERS Divisional Directors

Editor, IEEE Spectrum: Donald ChristiansenBOARD OF DIRECTORS, 1979 FA. Furfari(II) L.K. Anderson(IV) J.E. Barkle(VII) EducationalbField, Standards, and Technical SericR.E. Merwin(V( R. M. EmbersonPresident: J.J. Suran Regional Directors Publishing Services: E. K. Gannett

Executive Vice President: L. Young J.E. Shepherd(1) P.A.E. Rusche(4) D.C.J. Poortvliet(8) Professional Services: J. M. KinnSecretary-Treasurer: D.S. Brereton W.C. Farrell(2( D.L. Vines(5) C. Rivera-Abrams(9( Administration. C. F. Stewart, Jr.

Vice-Presidents R.H. Harris(3) C.A. Eldon(6) (to be appointed)(10)Educational Activities: B.J. Leon E.F. Glass(7) Board SecretanresProfessional Activities: B.O. Weinschel Director-Standards Activities: J. L. Koepfinger Awards: Una B. Lennon; Educational Activities:Publications Activities: R.W. Lucky Directors Emeritus: D. G. Fink; E. B. Robertson J. F. Wilhelm; Publications: E. K. Gannett;Regional Activities: P.F. Carroll Regional Activities: R. K. Asdal; Standards:Technical Activities: C.L. Hogan HEADQUARTERS STAFF I. G. Easton; Technical Activities: Neil D. Pundit;Junior Past President: I.A. Getting U.S. Activities: J. M. KinnSenior Past President: R.M. Saunders General Manager: Eric HerzExecutive Director: E. Herz Directors

Controller: T. W. Bartlett

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