IEEE TRANSACTIONS ON EDUCATION, VOL. 44, NO. 1, FEBRUARY 2001 41

An Interactive Multimedia System on “ComputerArchitecture, Organization, and Design”

Susamma Barua, Member, IEEE

Abstract—The multimedia system described in this paperdemonstrates the successful integration of multimedia into educa-tion and provides a clear example of how multimedia can be usedto deliver computer engineering and computer science concepts tothe often-diverse student base. The paper describes an interactive,knowledge-based multimedia system that has been used to teachusers about the basic aspects of computer architecture, organiza-tion, and design. The system is well suited for self-paced, studentdirected study, student review, and classroom presentation anddiscussion. The system allows learners to choose how informationwill be displayed, changing for example, among text, graphics,animation, and simulation. The hypermedia capabilities built intothe system enables it to respond based on the dynamic evaluationof both the contexts of the human–computer collaboration and theknowledge base underlying the visible screen presentation. Thesystem serves as a very useful aid to introduce and demonstratesome of the fundamental ideas of computer architecture andorganization.

Index Terms—Computer architecture, computer-based instruc-tion, interactive tutorial, multimedia system.

I. INTRODUCTION

M ULTIMEDIA—the integration of computers and com-munications has attracted the ever-increasing attention

of all walks of society and has already proved to have great im-pact on educational and industrial development [1], [2]. Withthe availability of multimedia computers, computer-based in-struction models that use intelligent simulation, dynamic links(on-line generation of links based on user behavior) and mul-timedia composition and creation can be developed. Examplesinclude the Explanation Planner [3], the Perseus Project [4], theInteractive Tutorial Software [5] and a number of Internet-basedtutorials. These models can be applied to such problems as sup-porting collaborative work, supporting information retrieval andbrowsing, illustrating complex concepts in science and engi-neering and augmenting teaching and learning. For example,the Explanation Planner is an interactive multimedia tutor thatparses typed student queries and plans the response with internalrepresentations before translating into natural language. The do-main knowledge for the Explanation Planner is basic electricityand electrical networks. The Perseus system is an aggregation oftexts, images, and programs related to the ancient Greek worldpublished as a set of HyperCard stacks and data files. Perseuswas designed as a research tool and medium of publication, as an

Manuscript received June 26, 1998; revised August 30, 2000.The author is with the Department of Computer Science, California State

University, Fullerton, CA 92834 USA.Publisher Item Identifier S 0018-9359(01)01254-7.

instructional aid for teachers, and as a self-directed learning en-vironment. The Interactive Tutorial Software is designed specif-ically for engineering education at the university level. It con-tains two different tutorial collections. The first contains tuto-rials on digital analysis for digital signal processing. The secondis a mathematical review and tutor in engineering.

The paper presented here describes an interactive knowl-edge-based system for teaching the basic aspects of computerarchitecture, organization, and design. The system, developedusing Macromedia Director, employs animation and simulationto achieve rich interactivity and to provide instant feedbackto users in response to their input. The complete system iscurrently available on the local network of the Department ofComputer Science at California State University, Fullerton. Thefirst three chapters described in the system are also availableon the Web at http://www.ecs.fullerton.edu/~sbarua. Studentsenrolled in the computer architecture courses offered by theDepartment can access the system. The interactive approachinherent in the system supports human–computer collaborationto satisfy user goals by effectively allowing the user to accessthe underlying knowledge base dependent on the user’s level ofunderstanding of the subject matter. This paper is organized asfollows: After discussing the need for the multimedia system,the paper presents an overview of the system layout and design.The paper then explains the evaluation methods employedto assess the effectiveness of the system in increased studentlearning and understanding of the subject material. The resultsfrom the use of the system over a two-year period are thendiscussed. Finally, the paper summarizes the results.

II. THE NEED FOR THEMULTIMEDIA SYSTEM

Interactive learning made accessible through multimediatechnology has proven to help learners improve their abilityto learn the related subject material [6]. Evaluation of someknowledge-based multimedia systems has shown that learnerscan advance to the same mastery level with these systems inone-third of the time required by conventional instructionalmethodology. In addition, learners have shown an improvementof 40% over the performance from classroom instruction[7]. Exceptional learning advances are possible, since knowl-edge-based multimedia systems can adapt learner responses totheir needs and foster instruction optimized for each.

The interactive multimedia system on “Computer architec-ture, organization, and design” was designed to encourage andhelp engineering and computer science students develop an in-tegrated understanding of basic concepts that are often ignoredwhile learning specific computational tasks. An integrated un-derstanding, in turn, enables students to visualize and connect

0018–9359/01$10.00 © 2001 IEEE

42 IEEE TRANSACTIONS ON EDUCATION, VOL. 44, NO. 1, FEBRUARY 2001

basic concepts that are usually presented in fragments in tra-ditional classroom lectures. The system facilitates this under-standing by presenting unified graphics or animation of con-cepts that bring together discussions generally found in severaldifferent textbook chapters. Information presented on the screenallows students to respond, thereby enabling them to broadentheir knowledge in that subject. This type of interaction, im-practical in books, lets students proceed at a pace appropriatefor their individual learning levels, and guides them throughlearning in a unique way, providing the individualization bestsuited to each student.

III. SYSTEM LAYOUT AND DESIGN

The domain knowledge for the multimedia system presentedhere is a broad introduction to the various aspects of computerarchitecture, organization, and design. The knowledge base ofthe system is divided into the following eight chapters:

• Chapter 1 Basic structure of a computer system;• Chapter 2 Control unit operation and design;• Chapter 3 The central processing unit;• Chapter 4 Internal and external memory;• Chapter 5 Demonstration of the instruction cycle of a

computer;• Chapter 6 CPU simulation;• Chapter 7 Input/output organization;• Chapter 8 Parallel processing.

The system’s style of learner interaction is inspired by theconcept that information is interconnected, can be shared amongpeople, and can be viewed in different ways [3], [6], [8]. Thepurpose of the system is to provide an environment in whichlearners can learn more effectively, using information presentedin a wide variety of media—textual as well as visual. The philos-ophy underlying the layout and design of the system presentedin this article is guided by the system’s objective in transmittingspecific skills and knowledge in such a way that learners will beable to demonstrate their mastery of the objective. This philos-ophy affects how the system was designed and how the systemmay be used. A well-designed self-instructional system shouldbe able to state what is it that the system must teach, and to iden-tify the materials and procedures that will work best to providethe information [9].

The system presents its knowledge base using one of fourscreens, the Main Menu screen, the Chapter Menu screen, theContent Page screen, and the Demonstration screen.

A. Main Menu, Chapter Menu, and Content Page Screens

The Main Menu screen, shown in Fig. 1, displays a “summaryof contents” of the system’s knowledge base. The chapter num-bers and titles are displayed as interactive buttons. The ChapterMenu screen displays a list of all the topics available under aspecific chapter. An example Chapter Menu screen is shown inFig. 2. Hypertext links are established for all the entries of aChapter Menu screen. The Content Page screens display the in-formation contained in various chapters. The system employstwo types of content pages. The first type is displayed whenthe learner clicks on a hypertext link. “Return” button is theonly button provided on this page. The “Return” button takes

Fig. 1. The Main Menu screen. The user can go directly to a specific chapterby clicking on the corresponding “Chapter number and title” button.

Fig. 2. Chapter 1 Menu screen. All entries use hyperlinks.

the learner back to the page from where the hypertext link wasestablished. Use of hypertext links within the system allows thelearner to navigate through the system and explore topics of in-terest on a need-to-know basis.

The system displays a second type of content page when thelearner clicks on the “Next” button instead of a hypertext link.The interactive buttons available on the resulting content pageare the “Back,” “Next,” “Main Menu,” and “Quit” buttons.

B. Demonstration Screen

Chapters 4, 5, and 6 of the multimedia system employ theDemonstration screens to display the micro-operations in-volved in:

BARUA: AN INTERACTIVE MULTIMEDIA SYSTEM ON “COMPUTER ARCHITECTURE, ORGANIZATION, AND DESIGN” 43

Fig. 3. The screen displayed by the system after it completes the fetch/decode cycle. Hypertext links are established for component and register names.

• the fetch/decode/execute cycles of a set of predefined ma-chine instructions;

• a memory access;• the CPU simulation.

The animation displayed on the demonstration screens is in-tended to make teaching machine level computer conceptseasier. The operations are demonstrated through the graphicalmovement of information from one component of the computerto another. This enables the learners to observe and understandthe micro-operations corresponding to the selected set of ma-chine instructions.

For example, when the learner activates the “Chapter 5Demonstration of the Instruction Cycle of a Computer” buttonfrom the Main Menu screen given in Fig. 1, the system firstrequests the user to choose one of the three cycles, namely,the fetch, decode, or the execute cycle. The system, then,demonstrates the micro-operations involved in the cycle thatthe user has chosen using the graphical movement of informa-tion (instructions or data) from one component of the computerto another. For example, if the learner requests the fetchcycle demo, the system first shows the graphical movementof information corresponding to the following sequence ofmicro-operations of the fetch/decode cycle:

MAR PC Load the address of the instruc-tion from the program counter(PC) to the memory address reg-ister (MAR).

MDR M[MAR] Read the memory locationpointed to by the MAR and storethe instruction in the memorydata register (MDR).

PC PC 1 Increment PC to point to the nextinstruction.

IR MDR Transfer the instruction fromMDR to the instruction register(IR).

EAR IR (Operand) Transfer the effective address ofthe operand from IR to the effec-tive address register (EAR).

The system then displays a summary of the sequence ofmicro-operations the computer has executed in order to com-plete the fetch cycle and the final contents of the registers thathave been affected by the execution of the fetch cycle as shownin Fig. 3. The learner can then request the system to repeat thedemonstration of the fetch cycle, or go on to the demonstrationof the execute cycle of one of the predefined instructions.The learner can also choose to return to the Main Menu, theWelcome Page, or exit the system. Fig. 4 shows the screen thatis displayed at the end of the execute cycle of the LDA (loadaccumulator) instruction.

C. CPU Simulation

The CPU Simulation discussed in Chapter 6 teaches studentshow to simulate a hypothetical Von Neumann computer archi-tecture at the register transfer level. The multimedia system,discussed in this paper, interacts with a commercially avail-able simulation package called “CPU Sim” to do the simulation.CPU Sim is available from Intellimation. The student first spec-ifies the details of the architecture to be simulated. The specifi-cations include the following items:

• names and lengths of all the registers that need to be pro-vided in the machine to be simulated;

44 IEEE TRANSACTIONS ON EDUCATION, VOL. 44, NO. 1, FEBRUARY 2001

Fig. 4. The screen displayed by the system after it completes the execute cycle for the LDA (load accumulator) instruction. Hypertext links are established forcomponent and register names.

• width and total number of memory locations;• instruction format to be used in the machine under simu-

lation;• machine instruction set to be used;• micro-instruction set needed to implement the fetch/de-

code/execute cycles of the instructions considered;• input–output channels needed.

The lecture classes and the information presented in Chapter6 of the multimedia system enable students to gain a completeunderstanding of the machine specifications that they need todevelop. After inputting items given in the list of specifications,students develop the sequence of microinstructions needed forthe fetch/decode cycle and the sequence of microinstructionsneeded for the execute cycles of the instructions defined in themachine instruction set. The multimedia system together withthe CPU Sim provide students the opportunity to analyze theeffect of adding new instructions to the instruction set, and en-able students to gain hands-on experience in writing microcode.

Students can test the architecture they simulated by runningtest programs written in assembly language. During the test pro-gram run, the simulator displays the contents of all the registersand the memory locations used by the test program. The simu-lator also allows one to single step through the program execu-tion, stopping the simulation after every clock cycle. The exe-cution can be stopped at any time to inspect the state of the ma-chine. One can also edit the contents of any component at anytime and then continue, or even back up one instruction at a timeall the way back to the initial state of the machine. This makesthe simulation environment a powerful tool for enhancing theinstruction on computer architecture and organization.

IV. A SSESSMENT OF THEEFFECTIVENESS OF THESYSTEM

The assessment plan was devised to determine the effective-ness of the system to teach in the hypermedia environments, andto increase student learning and understanding of the subjectmaterial. Evaluation efforts focused on teaching and learningquestions because these ultimately determined whether thesystem could be successful in enabling learners to improvetheir ability to learn the subject matter.

Assessment methods included

1) student surveys;2) classroom observations;3) discussions with students, individually and in small

groups;4) student performance on assignments, projects, and tests.

One hundred and twenty students were grouped into six studysections, 20 students per section, of a course on computer ar-chitecture, over a two-year period. The first two study sections(Group 1) did not use the system. The second two study sections(Group 2) used the system only as a self-directed learning andexploration tool, outside of the classroom. The last two sections(Group 3) attended classes where the system was used in classas a lecture/discussion tool and also used the system, outside ofthe classroom, as a self-directed learning tool. At the conclu-sion of the course, a survey was conducted. The students, whoused the system, were asked to give their opinions on the inter-active multimedia system, to provide suggestions on improvingthe system, and to propose ways by which the system could bebetter used in a classroom. Participation in the survey was volun-tary and anonymity was maintained for the responses. A total of80 responses were collected from the survey. In addition, the in-

BARUA: AN INTERACTIVE MULTIMEDIA SYSTEM ON “COMPUTER ARCHITECTURE, ORGANIZATION, AND DESIGN” 45

structor held discussions with students, individually and in smallgroups, outside the classroom, about their experiences with thesystem at three different times: early in their experience with thesystem, midway through the course, and at the conclusion of thecourse. Student performance on assignments, projects, and testswere also evaluated in the context of the experience differentsections had with the system. The results from student surveys,classroom observations, discussions with students, and studentperformance on assignments, projects, and tests were used toevaluate the learnability and usability and the effectiveness ofthe system as a self-directed learning and exploration tool andas a lecture/discussion tool.

V. RESULTS

This section describes the results obtained based on studentsurveys, classroom observations, discussions with students, andstudent performance on assignments, projects, and tests. Thesurvey included a total of eight questions that focused on theeffectiveness of the system in teaching and learning. Classroomobservations were based on student responses in the classroomduring course lectures/discussions. In addition, discussionswere held with students to get a better understanding of theirexperiences with the system and how effective the system wasas a self-directed learning and exploration tool.

A. Student Surveys

Students were asked to rate the questions, given in Table I, ona scale of 1 to 5. Student responses are given in Table II.

The student responses were very positive. A large number ofstudents confirmed the system’s ability to stimulate interest inexploring the subject matter and to promote integrated under-standing of the subject matter. Responses to question 3 showthat the visual representation and the movement of informationfrom one component of the computer to another served as anextremely effective aid in learning machine-level computer con-cepts. The system was rated high for its capacity to present in-formation clearly, and to provide direct, fast, and easy access toinformation. The survey also indicated that the system is a valu-able supplement to the course on computer system architectureand is effective as a self-paced, self-directed learning tool. Avast majority of the students also agreed that the system pro-vided adequate human–computer interaction.

B. Classroom Observations

Instructor’s notes on student responses in the classroomduring course lectures/discussions revealed that the studentswho used the system were better prepared for the lessons thatfollowed. Sample notes include, “students in Groups 2 and 3demonstrated more confidence and completed the design inless time when asked to design a control unit for a computerthat has an architecture and instruction set different from theone covered in the class,” “students in Group 3 became familiarwith the cache and virtual memory concepts in just one lecture(one hour and fifteen minutes), whereas, Group 2 took abouttwo hours, and Group 1 about 3 lectures,” and “the animationassociated with instruction pipelining (Chapter 8) made it easyto discuss the pipelining concepts in the class.” In general,

TABLE IQUESTIONSASKED IN THE SURVEY

TABLE IIRESPONSE TO THESURVEY

the animations displayed on the demonstration screens madeit easier for the instructor to teach machine level computerconcepts.

C. Discussions with Students

During several discussion sessions, the students stronglyagreed in reporting that the system provided an improvedlearning environment. Students also stated that the use ofhypertext links established in the system allowed them tocreate personal pathways through a lesson, thereby enablingthem to explore topics of interest. One of the advantages ofthe system that was pointed out was that the system provideddirect, fast, and easy access to textual and visual informationon a variety of topics in computer architecture, organization,and design. The student responses to the animation techniquesemployed by the system were very positive. Students thoughtthe demonstrations given by the system and the simulationcapabilities built into the system made the concepts andoperations underlying the instruction cycle, cache memoryaccess, and pipelining much clearer. One of the limitations ofthe system, as pointed out by the students during a discussion

46 IEEE TRANSACTIONS ON EDUCATION, VOL. 44, NO. 1, FEBRUARY 2001

session conducted at the conclusion of the course, is the lack ofa keyword/topic/graphic/animation search tool. This tool wouldenable the system to quickly locate words, topics, graphicsand animations of interest instead of the learner’s having tonavigate through the Main and Chapter Menus. Developmentof such a tool is planned as an improvement for the futureversion of the system.

D. Student Performance

Students from those sections who used the system demon-strated significantly better understanding of the computer con-cepts in general. The performance of students in Groups 2 and3, on assignments, tests, and class projects, were consistentlybetter than those in Group 1. The overall scores (based on as-signments, tests, and class projects) for students in Groups 2 and3 were 35% more than the students in Group 1.

VI. CONCLUSION

The multimedia system on “computer architecture, or-ganization, and design” provides an integrated multimedialearning environment in which learners are allowed to choosehow information is displayed, selecting for example, amongtext, graphics, or animation. The system can be used as aself-directed learning tool and as a class lecture/discussion tool.The multimedia system is beneficial to computer engineering,computer science, and electrical engineering students and alsoto anyone who would like to gain an understanding of thehardware and software concepts of computers in general. Thegenerous use of the hypertext links, established in the system,enables the system to respond, based on dynamic evaluation ofboth the contexts of the human–computer interaction and theknowledge base underlying the visible screen presentations.

The animation provided in the system serves as a very practicaland effective aid to introducing the concepts of how a computeroperates at the machine level.

REFERENCES

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[3] M. Cornell, M. Woolf, and D. Suthers, “Using live information in a mul-timedia framework,” inIntelligent Multimedia Interfaces, M. Mayburry,Ed. Menlo Park, CA: AAAI/MIT Press, 1993, pp. 307–327.

[4] G. Marchionini and G. Crane, “Evaluating hypermedia and learning:Methods and results from the perseus project,”ACM Trans. Inform.Syst., vol. 12, no. 1, pp. 5–34, Jan. 1994.

[5] S. L. Wood, “A new approach to interactive tutorial software for en-gineering education,”IEEE Trans. Educ., vol. 39, no. 3, pp. 399–408,August 1996.

[6] R. C. Schank, “Active learning through multimedia,”IEEE Multimedia,vol. 1, no. 1, pp. 69–78, Spring 1994.

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[9] A. C. Luther,Authoring Interactive Multimedia. Cambridge, MA: APProfession, 1994, pp. 1–94.

Susamma Barua(S’86–M’88) received the Ph.D. degree in computer engi-neering from University of Cincinnati, Cincinnati, OH, in 1988.

She is an Associate Professor in the Department of Computer Science atCalifornia State University, Fullerton. Her current research areas include com-puter performance evaluation, web-based database systems, and computer net-working. She has published a number of papers in her research areas.

Dr. Barua received the “Outstanding Recognition Award for Creative andScholarly Activity” in March 1998 from California State University, Fullerton.She is a member of the ACM.