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Calhoun: The NPS Institutional Archive Theses and Dissertations Thesis Collection 1981 Adaptation of magnetic bubble memory in a standard microcomputer environment Hicklin, Michael S. Monterey, California. Naval Postgraduate School http://hdl.handle.net/10945/20407 %M\- '('''''•''-• ,v?j'' -'''"I- IK?:<J,e4;^/>':f';^.•^''' >if"4';r;.'i.'''; „ " ? ..^' V V DUDLEY KNOX LIBRARY NAVAL P^STCr^-iJATE SCHOOL MONiEmE,, CA;..F. 93940 NAVAL POSTGRADUATE SCHOOL Monterey, California THESIS ADAPTATION OF MAGNETIC BUBBLE MEMORY IN A STANDARD MICROCOMPUTER ENVIRONMENT by Michael S. Hicklin and Jeffrey A. Neufeld December 1981 Thesis Advisor: R- R. Stilwell Approved for public release; distribution unlimited T20Z 1 ; IINCT^SSTFTED SKCuniTV CLASSiriCATlOM OF THIS ^ACe fWhmit 0«« Enlmfd) READ INSTRUCTTONS REPORT DOCUMENTATION PAGE BEFORE COMPLETTNO FORM \ nIpONT NUMaCM 2. OOVT ACCKtSiOM NO. 1 *eCl^ltNT"S CATALOG NUMBER 4. Sublltlmi 5. TITLE fmta TYPE OF REPORT ft PEOtOO COWERED Mas ter ' s Thesis Adaptation of Magnetic Bubble Memory in December 1981 a Standard Microcomputer Environment • . Pe«FO«MINO ORG. REPORT NUMSCR 7. AuThONi'*> • . CONTRACT OR GRANT NLMSCRC*; Michael S, Hicklin Jeffrey A, Neuf eld * PCMFOffMIMa OnOANlZATION NAMC ANO AOOMCtS 10. PROGRAM ELEMENT PROJECT T*S< AREA « WORK UNIT NUMBERS Naval Postgraduate School Monterey, California 93940 n CONTROLLING OFFICE NAMC AND AODMCSt 12. REPORT OATE Naval Postgraduate School December 1981 Monterey, California 93940 IS NUMBER OF PACES U MONlTOHiNC AGENCY NAME * AOORCStC'/ aillarwnt tram Catttroltlni OHIe») IS. SECUNITY CLASS, (ol Ihit r*>ortj Naval Postgraduate School Unclas s if ied Monterey, California 93940 rSa. OCCLASSIFICATION/ OOWNGRAOlNG SCHCOULC l«. OlSTRlSUTtON STATEMENT re/ tM« Ktptrt) Approved for public release; distribution unlimited 17. DISTRIBUTION STATEMENT (ot (/•• •**«r«e( cfilcrvd In Block 30. II dllUrmnI Iram Hmport) I*. SUPPLEMENTARY NOTES 19. KEY WORDS (Coniinu* art tmr»f »ldm tl naemaamtr fd Idonilly »r Mock nwmkor) Magnetic bubble memory, microcomputer operating svstem, CP/M-86, secondary storage media 20. ABSTRACT (Conilinio on ravara* aida // nococmmr antf Idotnltr kr klock mmtkot) Magnetic bubble memory is a new digital storage technology that offers many significant advantages over currently existing secondary storage media. Bubble memories, with high densities and relatively fast access times, are non-volatile semiconductor devices that provide a high degree of reliability in harsh environments. This technology has the potential for a vital and unique role in FORM EDITION OF I NOV <• IS OBSOLETE DO I jAN 7 , 1473 S/N a 102-0 14- $60 -^iCLA.'^f^Ty^"]^ SECURITY CLASSIFICATION OF 'HIS PAGE '»^a«l Daia Jtniorod) UNCLASSIFIED l'**^«M rtat* •m****^ (continuation of abstract) both the civilian and military computing environments due to the combination of characteristics exhibited by magnetic domain devices. This thesis presents an implementation of a magnetic bubble device utilizing a conventional operating system, Digital Research's CP/M-86, and a standard commercial 16-bit microcomputer, the Intel iSBC 86/]2A. A fully operational system capable of testing, evaluating and utilizing a magnetic bubble device in a standard user environment is presented . DD Fornj 1473 UNCLASSinzD Approved for public release; distribution unlimited. Adaptation of Magnetic Bubble Memory in a Standard Microcomputer Environment by Michael S. fjicklin Captain, United States Marine Corps B.S.M.E., University of Utah Jeffrey A, Neufeld Captain, United States Marine Corps B.S.S.E., United States Naval Academy Submitted in partial fulfillment of the requirements for the degree of MASTER OP SCIENCE IN COMPOTEB SCIENCE from the NAVAL POSTGRADUATE SCHOOL December 1981 DUDLEY KNOX LIBRARY NAVAL POSTGRADUATE SCHOOL MONTEREY, CAUF. 99HQ^^ AfiSTBACT .Magnetic bubble memcry is a new digital storage technology that offers many significant advantages over currently existing secondary storage media. Bubble memories, with high densities and relatively fast access timss, are non-volatile semiconductor devices that provide a high degree cf reliability in harsh environments. This technology has the potential for a vital and unigue role in both the civilian and military computing environments due to the combination of characteristics exhibited by magnetic domain devices. This thesis presents an implementation of a magnetic buttle device utilizing a conventional operating system. Digital Research's CP/M-86, and a standard commercial 16-bir microcomputer, the Intel iSBC 86/12A. A fully operational system capable of testing, evaluating and utilizing a magnetic bubble device in a standard user environment is presented. ' TABLE CF CONTENTS I. INTRODUCTION 9 II. BACKGROUND OF HUBBLE MEMOFIES 12 A. MAGNETIC BOBBLE DOMAINS 12 B. BUBBLE DOMAIN DEVICES 17 C. HISTORY AND DEVELOPMENT 25 D. CURRENT TECHNOLOGY AND ARCHITECTURE 27 III. APPLICABILITY OF MAGNETIC BOBBLE MEMORIES 36 A. COMPARISON CF MASS STORAGE TECHNOLOGIES 36 B. APPLICATIONS OF MAGNETIC BUBBLE MEMORY 42 IV. DESCRIPTION OF THE DEVELOPMENTAL SYSTEM — 46 A. TIB0203 MAGNETIC BUBBLE MEMORY 46 B. PC/M MBB-80 BUBBLE MEMORY SYSTEM 48 C. DEVELOPMENTAL SYSTEM 50 D. IMPLEMENTATION HOST SYSTEM 52 V. LOW-LEVEL BUBBLE DEVICE INTERFACE 56 A. INTEL 8080 IMPLEMENTATION 56 3. USE OF THE CP/M-80 MBE-80 DIAGNOSTIC PROGRAM — 60 C. INTEL 8086 INTERFACE CONSIDERATIONS 62 D. INTEL 8086 IMPLEMENTATION 65 E. USE OF THE CP/M-86 aBB-80 DIAGNOSTIC PROGRAMS - 71 ^I. CP/M-86 INTERFACE IMPLEMENTATION 75 A. BOBBLE DEVICE STOBAGE ORGANIZATION 75 B. CP/M-86 BIOS CONSIDERATIONS 79 1. Structured Standards for the BIOS 79 2. Structured Approach to the BIOS 81 3. Jump Vector Interfaces 84 C. aSE OF THE CP/M-86 MEB-80 FORMAT PROGRAM 88 D. CP/M-86 BIOS IMPLEMENTATION 90 1. Modification of the Existing BIOS 90 2. Disk Parameter Table 92 3. Disk Configuration Tables 95 !* . BIOS Generation Procedure 99 5. Reconfiguring the BIOS 101 E. EVALOATION OP THE IMPLEMENTATION 102 1. Performance 102 2. Limitations 105 3. Applications 107 II. 300TL0ADING CP/M-86 FROM THE MEB-80 109 A. BOOT ROM AND LOADER CONSIDERATIONS 109 B. BOOT ROM AND LOADER IMPLEMENTATION 112 C. SPRCM GENERATION 115 VIII. CONCLUSIONS 118 A. IMPLEMENTATION SYNOPSIS 118 B. RECOMMENDATIONS FOR FUTURE WORK 120 t C. POTENTIAL APPLICATIONS 122 APPENDIX A PROGRAM LISTING OF DIAG80.ASM 126 APPENDIX B PROGRAM LISTING OF DIAG86S.A86 135 APPENDIX C PROGRAM LISTING OF DIAG86M.A86 146 APPENDIX D PROGRAM LISTING OF MB80FMT.A86 159 APPENDIX E PROGRAM LISTING OF MBBIOS.A86 166 APPENDIX F PROGRAM LISTING OF MB80ROM.A86 187 LIST OF REFERENCES 196 INITIAL DISTRIBUTION LIST •' 198 DISCLAinER Many tarms used in this thesis are registered trademarks cf ccmmercial products. Rather than attempt to cite each individual occurrence of a trademark, all registered trademarks appearing in this thesis will be listed below, following the firm holding the trademark. Intel Corporation, Santa Clara, California: Intel HOLTIBUS INTELLEC MDS Intel 8080 Intel 8086 iSBC 86/12A iSBC 202 i8259 Pacific Cyber/Metrixs Incorporated, Dublin, California: Eubbl-Tec Bubbl-Machine MBB-80 Bubbl-Board Digital Research, Pacific Grove, California: CP/M-80 CP/M-86 CP/M I. IMTRODOCTIQN Magnetic bubble memory is a new digital storage technology that offers many significant advantages over currently existing secondary storage mediums. Bubble raencries, with high densities and reiauively fast access tines, are non-volatile semiconductor devices that provide a high degree of reliability in harsh environments. This technology has the potential for a vital and unique role in both the civilian and military computing environments due to the combination of characteristics exhibited by magnetic dcnain devices. This thesis presents an itcplementation of a magnetic bubble device (M3B-80) utilizing a conventional operating syst=m (CP/M-86) and a commercial 16-bit microprocessor (Intel 8086) . A fully operational system capable of testing, evaluating, and utilizing a magnetic bubble device in a standard user environient is presented. There are four major phases inro which this thesis is organized. The first phase will present an overview of bubble domain devices tc provide an understanding and evaluation of their potential applications as mass storage lediums. Chapter II will describe the theory of magnetic butble devices and the current state of magnetic dooain Technology. Chapter III will present an evaluation of bubfcls memory technology and utilization along with a justification for the applicability of magnetic bubble devices. The second phase will address the low-level interface requirements for the MBB-80 Bubbl-Bcard (produced by PC/M Inc.) when interfacing with either the Intel 8080 or Intel 8086 microprocessor. The purpose of this phase will be to: (1) verify the operational characteristics of the MBB-80; and, (2) design and implement the low-level systems software necessary to interface the operating system's I/O structure with the magnetic bubble menoory ccntrcller. The third phase will address the issues necessary to implement the interface of the bubble memory system with the operating system's primitive secondary storage access routines. The tasks necessary in this phase are to: (1) design a memory organization and management scheme for the magnetic bubble memory; and, (2) design the interface such that the magnetic bubble memory appears as a "standard" mass storage device (disJc) to the host operating system. The fourth phase is the actual interface of the MBB-80 Bubbl-Boards into the
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