Using Programmable CaIculators Reed D. Taylor and Historical Perspective Michael W. Woolverton Present computers operate thousands of'times faster than the first models and at a fraction of the cost per unit Introduction of work accomplished. They are easier to access. more The collection and manipulation of data to provide accurate and reliable, simpler to program. less sensitive relevant information has become extremely important to to environmental conditions, and occupy less space per decision makers in agriculture. The amount of data has unit of capacity. proliferated and calculations have become more com- Two developments ot'special significance to agricul- plex, causing increased reliance on electronic data pro- ture have been time-sharing and the advanced pro- cessing ' systems. Rapid development of computer grammable calculator (hand computer). Time-sharing. technology has now literally placed the power of the com- in its broadest sense, allows one almost instant access to puter in the hands of decision makers. Instead of work- computer programs and data banks at any location from ing through computer specialists. operating managers any location. All that is needed is a terminal, a telephone. find themselves able to call forth information directly electrical current, arid a contract with the appropriate from computers in order to make rapid decisions. computer center. This development of the late 60s and early 70s was especially significant to agriculture as it While the elimination of time delay and reduction of allowed typically small agricultural firms (farm and non- human communication problems has improved time- farm) and the various State Cooperative Extension Ser- liness and reliability of information available for decision vices access to computer technology at various locations making, there is a greater burden on decision makers in at relatively low cost. small and medium sized agricultural firms. They now must understand both the use of computerized informa- Battery powered hand held calculators first became tion systems in decision making and basic computer available in the early 1970s. Now programmable technology and have the skills to operate equipment calculators are sophisticated computers. Many of the available to them. programs previously available through time-sharing are available on programmable calculators. These units pro- This pervasive impact of cybernetics on the agricul- vide access to computer capability at very low cost. An tural and non-agricultural economy uniquely challenges advanced programmable calculator can be purchased for the educational community. In fact, the National Science about $200.00, a compatable printer for about $150.00, Foundation stresses that due to the high potential for in- and an agricultural exchangeable module for about fluencing the nation positively, teaching students with $40.00, for a total outlay of about $400.00. Costs of scientific majors basic computer principles and concepts operation are negligible. should receive high priority for use of educational re- sources over the next decade (National Science Founda- The future will see more miniaturization of hand tion. 1979). The Foundation concludes that development held units. Some experts believe that VLSl (Very Large of appropriate educational programs is not only desir- Scale Integration) will make it possible, perhaps within able, but inevitable and that federal funds and influence five years, to compress the number-handling proficiency should be expended to accelerate the process. of a modern, large computer into a single part about the size of a match head. The advent of such "superchips' The conclusions of the National Science Foundation could prove to be the technological equivalent of the leap on preparing students for a "computerized world" were from transistors to integrated circuits in the early 1%0s. anticipated by agriculturists. In 1972, the course "Com- (Shaffer. 1979). puters in Agricultural Decisions" was introduced at The Ohio State University. Since its inception it has evolved Educational Objectives in response to student needs and rapid technological ad- "Computers in Agricultural Decisions" at The Ohio vances. State University is a tirst course in applied computer Taylor and Woolverton are members of the Department of Agricultural techniques. The overall objective of the course is to de- Economics and Rural Sociology. Ohio Agricultural Research and Dc- velop in students the ability to solve agricultural decision velopment Center, the Ohio State University, Columbus. making problems with the help of computer systems. The

NACTA Journal - June 1980 problem solving approach is taught as a four step limit on the number of programming steps ad the sequence: 1) problem analysis, 2) flowchart application, amount of data that can be entered. 3) coding and executing the program, and 4) documenta- Late model programmable calculators allow users to tion. save programs, and the contents of memory registers on The specific educational objective in problem read/write media, magnetic cards in the case of the TI- analysis is for students to demonstrate an understanding 59. Thus users can save for future use an unlimited num- of the role computer systems can play in the recognition ber of programs. To solve a particular problem, a user of a problem, identifying the cause of the problem. and loads a program into the hand computer simply by hav- analyzing alternative solutions. Emphasis is placed on ing the unit read magnetic cards. Data may be entered by the design of feasible management information systems. hand or from magnetic cards. A second educational objective is to develop the ability to use program and system flowcharting techni- Modules Available ques in problem solving. Students use the four major flowcharting techniques - initialization, looping, de- Commonly used programs are often available on veloping a sum, and developing a counter to formulate a modules, each containing about 25 programs. These pro- graphic representation of operations and decision logic grams or portions of them can be used individually in required to solve problems in their particular agricultur- program solving and can also be used as 'subroutines' in al specialties. individually written programs. This subroutine capability greatly increases the potential scope of user A major portion of the course is devoted to the third written programs. step in problem solving - coding and executing the pro- Concepts and skills learned and developed by stu- gram. The specific educational objective here is for stu- dents in working with hand computers ease the transition dents to demonstrate a working knowledge of software to mini-computers, timesharing, and mainframe units. elements and hardware components that make up com- For example. in using the programmable calculator. stu- puter systems. Studying computer number systems, ,dents must assign locations for both instructiotls and languages, and programming contributes to the objec- data and make provisions for recall from assigned loca- tive. Comparison of design characteristics and cap- tions. This requirement, which in a large computer is abilities of various computers (e.g. main frame systems, automatically handled by a compiler, makes students time-sharing, mini-computers, and hand held units) also more aware of basic computer operations. aids students in reaching this specific educational ob- Manufacturers will maintain upward compatibility jective. As they organize information for decision mak- in new models with hand held computers of the future ing. students recognize the importance of documenta- utilizing many of the features of present models. for tion, the fourth and final step in problem solving. example key layout. Students becoming proficient in the use of present models should find little difKculty in up- Programmable Characteristics grading to newer, more powerful eguipment. Recent development of advanced programmable Educators are constantly reminded of budget limita- tions. Compared to other automatic data processing calculators holds promise as a means to help meet educa- equipment, the cost of providing "hands-on experience" tional objectives. New models are programmable, allow with programmable calculators is very low. Cost com- preservation of programs and data on read/write media, have solid state exchangeable program modules. allow parisons will be made in a later section. upward compatibility in both learning and new hardware Providing students with what amounts to their own introduction, are low cost, portable, and offer versatility personal computer adds greatly to their satisfaction with in usage. The unit purchased for use in the course was the course. Portability of the units means they can be the Texas Instruments model 59. Models with similar used in the classroom and can even be checked out ofthe capabilities are available from other manufacturers. library on demand by students. For example, the TI-59 weighs less than a pound and can operate for about three Programmability is the most attractive feature of, hours on a battery charge. these units. Fairly sophisticated programs can be de- Versatility of programmable calculators also adds veloped and executed. Because the units can be pro- satisfaction by enabling students to acquire knowledge grammed, students using a TI-59 or similar programm- from a pre-existing base. A programmable calculator can able calculator can write, code. and execute programs. be used by students simply as a calculator or as a com- The graphic representation of the problem to be solved, puter using internal programs contained in exchangeable i.e. the flowchart. takes on new meaning when pr'ogram modules, programs developed by other agriculturists steps and data are entered into the unit. Execution pro- which are entered by coding, and programs written by vides immediate feedback to students. Applications re- students themselves. This progression on the machine quiring numerous calculations can be handled with little from use as a calculator to self programming can ease difficulty. However, the small memory compared to more student transition into the sometimes intimidating world sophisticated computer systems does place an upward of computers.

NACTA Journal - June 1980 Availability of Programs Table 1. Materials Included in Library Check Out An important factor in any computer system is Vinyl Portfolio Transport Case (Hare1 G8-R105-46) availability of appropriate programs for use in solving Programmable Calculator (Texas Instruments TI-59) problems. Fortunately, development of programmable AC adapterlcharger 120 Vac calculator programs for agricultural applications has Master Library Book with Module been rapid. Many programs written for other computer Agricultural Library Book with Module Personal Programming Book provided by the Equipment systems were easily adaptable to the compact units. Agri- Manufacturer cultural extension specialists at Iowa State University led Programmable TI 58/59 Solid State Software Libraries and Other the way in this conversion and in the development of new Accessories Booklet programs. They started a subscription service whereby users can obtain a large number of current programs and wards, in their extension experience, also found one also obtain new programs as they are released (Iowa calculator for each two participants in workshops to be State, 1978). Agricultural extension specialists at Cornell ideal (McGrann, 1979). The major utility of printers is in University have also developed programs that are avail- writing and debugging programs. When the equipment able through the Northeast Regional Agricultural is not being used in discussion/laboratory sessions, it is Engineering Service on a subscription basis (Northeast available to students through the Agriculture Library's Regional Agricultural Engineering Service. 1978). closed reserve system. Students are able to check out a When Texas Instruments became aware of the wide- 'computer packet' (Table 1) anytime the library is open spread use of the TI-59 by agriculturalists they commis- and units are available. Use is restricted to the library. sioned Iowa State University to refine sixteen of the most A term project of ten to twenty pages plus an oral commonly used agricultural programs for inclusion in presentation of the project is required of each student. an exchangeable agricultural module (McGrann, 1979). Students may choose any topic, broad or narrow, that The module is now available conimercially along with ten relates concepts and techniques taught in the course to other exchangeable modules (master library, applied their personal area of interest. Most students use existing statistics, real estate and investment, aviation, marine programs or write special programs for the programm- navigation, surveying, leisure library, securities analysis. able calculator as a portion of their term projects. Each business decisions, and custom library information) student is allocated ten minutes in a special interest dis- which offer users a wide range of programs in many dif- cussion/laboratory section to present a summary of the ferent subject matter areas. term project. In addition to the modules, Texas Instruments of- For discussion purposes, the course sequence can be fers specialty packets which are collections of programs divided into three parts: 1) introduction to programm- designed for special interest groups that the user keys in- able calculators, programming, problem solving. and to the calculator. Finally, one can join user groups where- automatic data processing: 2) computer languages and in an individual may both contribute and receive pro- more advanced programming; 3) basic computer prin- grams. ciples. Anatomy of the Course Table 2. Selected Characteristics of Students Completing Enrolln~entis limited to 86 students (room capacity) "Computers in Agricultural Decisions", Spring and Autumn Quarters 1979. each quarter, with student demand exceeding capacity most quarters. All students meet together three periods Quarter s~l.fng Autumn per week for lecture. The class is then divided into four Nuniber of Students 68 76 groups, based on subject matter interest, for discus- Clus Rank Percent Percent sion/laboratory periods. Sections include horticulture, Seniors 30 32 animal industries, crop production. and agricultural Juniors 32 30 business. Each group meets once a week for a two hour Sophomores 26 38 Freshmen 12 0 period, Students are required to purchase two texts for Mdor Percent Percent the course. The first. Introduclion to the Computer: The Animal Science 30 I8 Tool of Business introduces them to basic computer con- Agricultural Economics 29 28 cepts (Fuori, 1977). The second, Programmable Calcula- Horticulture 16 22 Agricultural Education 10 9 tom: Business Applications discusses the equipment Dairy Science 4 4 being used (Aronofsky. 1978). Agronomy 4 7 Experience has shown that an ideal complement of Agriculturctl Conlmunications 3 4 equipment for the course is 15 programmable calculators Poultry Science 2 0 with an agricultural module for each and 10 compatible Agricultural Mechanization printers. This allows one calculator for each two students and Systems 2 8 Sex Percent Percent in the discussion/laboratory sections, one for the instruc- Male 68 66 tor, and three spares to handle unusually large sections Female 32 34 and to replace units being repaired. McGrann and Ed- NACTA Journal - June 1980 The equipment and its operation effectively attracts The final third of the quarter is spent learning basic the students' attention. To take advantage of this, stu- computer principles. After students become proficient dents are introduced to the programmable calculator in operators and problem solvers using programmable the first discussion/laboratory section. In a workshop calculators, they seem to have little trouble transfering setting students are asked to store values in memory reg- similar procedures to more sophisticated equipment. In isters, perform mathematical calculations recalling this section, students are introduced to computer num- specific values from appropriate registers, and then ac- ber systems, the history of computers, processing and cumulate results in still other memory registers. This ap- storage devices, input/output media and devices, ad- proach acquaints students with data processing, intro- vanced computer concepts and anticipated future de- duces them to the equipment, and builds rapport be- velopments. Discussion/laboratory sections are devoted tween the instructor and students as well as among stu- to programming in BASIC and to oral presentations by dents. students of term projects. Next, students learn simple programming on the Ohio State Experience programmable calculators. Students learn that a pro- The need to educate agricultural students in com- gram is simply a method of getting the equipment, not puter technology and its application to agriculture was humans. to do the work of pressing buttons and writing recognized at Ohio State at the beginning of the decade. down intermediate results. In the discussion/laboratory A course was taught on an experimental basis during periods, the assignment is to write a simple prograni to Winter Quarters 1972 and 1973. It was officially intro- do the same mathematics done manually the previous duced as "Computers in Agricultural Decisions," week. autumn quarter 1973. Since then it has been taught each autumn. winter, and spring quarter. Studenk were grant- Students then learn to use magnetic cards to store ed the option of using credit hours earned from the programs and data off-line and to use the printer. After course to help meet basic College of Agriculture require- writing and debugging programs without these accessor- ments in the category of mathematics, computer science, ies, students appreciate their contribution. With this statistics, or accounting. Allowing students to count background they are introduced to flowcharting in "Computers in Agricultural Decisions" toward the modeling as an approach to problem definition and "math" option has contributed to a very heterogenous analysis. The previous work with the programmable class composition (Table 2). Even with heterogeneity calculator serves as a bridge to relate flowcharting sym- there was little difference in class performance according bols to identifiable programming steps. to class rank (Table 3). The middle third of the course concentrates on pro- Numerous changes have been made since inception gramming and applied problem solving. During this time of the course. It was changed from three to five credits students are first introduced to the general framework of starting autumn quarter 1975. Autumn 1977, the course computer languages. Next, they learn more sophisticated format was changed from all lectures to three periods of programming which includes internal decision making lecture per week plus one two-hour discussion/laboratory through maintaining a counter, branching, and looping. session. While this was an improvement. the change was They are also introduced to the BASIC language by using not as effective as hoped. The heterogeneity of student time-sharing. This demonstrates the similarities and dif- interest reduced the effectiveness of laboratory de- ferences between machine specific and high level com- monstrations. For example. animal science students puter languages. Discussion/laboratory sections are de- could not or would not relate to the demonstration of a voted to application problem solving and one major as- horticulture computer program and vice versa. This signment wherein each student writes a fairly sophisticat- situation was rectified by making the discussion/labora- ed program on the calculator, using the techniques learn- tory sections subject matter oriented beginning Spring ed, to solve an agricultural problem. Quarter 1978.

Table 3. Average Grade Point and Class Rank Total Freshmen Sophoniores Juniors Seniors Reported Nonclassroom Stndent Time S A S AS A S AS A ,Expended on the Course, Spring and Numberof Students Reporting 65 71 8 0 17 26 20 23 20 22 Antrimn Quarter, 1979. Average Grade Point 2.8 2.9 3.0 - 2.8 2.9 2.7 2.9 2.8 2.9 Average Total Hours Expended Outside the Classroom 59 69 58 - 53 75 63 60 59 70 Average Houn Expended Outside the Classroom Operating the Programmable 11 W 3 31 42 36 32 32 39 Spring Quarter 1979 Autumn Quarter 1079 Based on a four point system (A4. B=3. C=2. D= I. E=O)

NACTA Journal - June 1980 Changes have also occurred in the means by which Table 4. Capital Investment for Data Processing Equip- students are provided "hands-on experience" with con]- ment and Costs for Depreciation, Repairs, and Replace- puter equipment. Providing this experience to students ment. in a problem solving atmosphere has been a goal since Life Yearly Yearly Repr. the introduction of the course. Due to budgetary limita- Item Cost Length Depr. and Reol. tions and access difficulties with both hardware and suit- dollars yea& dollars doll& able terminal was brought into the classroom to access Promammable- calcu- agriculturally oriented computer programs on various Iators (Texas lnstru- able terminal was brought into the classroom to access ments-TI-59) 15 at 5204.00 3060.00 5 612.00 459.00 agriculturally oriented computer programs on various Printers (Texas In- computer systems (i.e. Telplan, CMS. Com-Share, Ohio struments-PC-100C) State, etc.) on a time-sharing basis. While this approach I0 at $148.00 1480.00 5 296.00 222.00 was useful, it fell far short of the goal of offering prac- Agricultural module tically unlimited individual student access to appropriate (Texas Instruments/ Iowa State) hardware and suitable problem solving software. Ad- 15 at 537.50 562.50 5 1 12.500 84.37 vanced programmable calculators. first used Winter Portfolio transport Quarter 1979, have provided a means of reaching this cases goal. 15atS14.06 210.90 42.18 31.64 Utilizing. programmable calculators provided stu- Extension Cords 50.00 5 10.00 7.50 TOTAL 5363.40 1072.68 804.51 dents with virtually unlimited "hands-on experience" at : tual 1979 costs. extremely low cost. During Autumn Quarter 1979, for b Zero salvage value. example, students averaged 38 hours each of computing 1570 per year. time outside the classroom by checking the computer packets out of library closed reserve. Table 4 shows the half of the outside time was spent operating the investment and depreciation, repairs, and replacement calculators (Table 3). charges for the equipment. A five year life length was Summary and Recommendations estimated due to unlimited student access and ob- solescence. Additional overhead items such as library Rapid advancement of cybernetic technology has costs and electricity are not included. Quarterly costs for presented a unique challenge to educators. First, the equipment can be budgeted at about $740.00 (Table 5). technology has become pex-vasive, effecting all aspects 01 Based on time of 43 hours per student, the direct cost per the economy. For students, both agriculture and non- hour was about twenty cents. agriculture, to be adequately prepared to function ef- To get a better measurement of student reaction to fectively in the "computerized world" of the present and the programmable calculator and the course as it is now future they need a basic education in the principles and taught, students were asked to complete a questionnaire concepts of computers and related information technology. They also need to know how to apply it in during the last week of Autumn Quarter 1979. All but two of the 76 students completed evaluations. Students their particular areas of specialization. Secondly, the were enthusiastic about the use of the programmable technology has provided a means of achieving this educa- tion at relatively low cost. calculator. All but one rated it as either essential, very Based on The Ohio State University experience. the important, or important when asked "How important following recommendations to educators contemplating was access to and utilization of the TI-59 to your compre- a similar course are offered by the authors. First. if class hension of computers and their present and future composition is heterogeneous. create subject matter utilization in agriculture and society?" The remaining oriented discussion/laboratory sections each limited to student rated it as slightly important. No one rated it as not important. Eighty-six percent of all students ranked it in the top five when asked "compared to all other cour- Table 5. Annual Costs, Costs per Student Hour Taught, ses you have taken at Ohio State, how would you rank and Costs ner Hour of "Hands on Experience." "Computers in Agricultural Decisions" as to its utility in Cost per- Cost per l-iour preparing you for your future?" This figure ranged from Annual Student Hour of "Hands on 92 percent for Sophomores to 73 percent for Seniors Item Cost Tau~ht Experience" (Table 6). Students also found the course demanding. Fixed Costs Depreciation 51072.68 50.84 SO. 10 When asked "Compared to all other courses you have Repairs and replacement 804.51 0.63 0.07 taken at Ohio State i ow would you rank 'Computers in Variable Costs Agricultural Decisions' as to the amount of effort re- Printer paper quired to meet course objectives?", ninety-seven percent 100 rolls at ranked it in the top five. Students reported spending an 53.40 340.00 0.27 0.03 TOTAL 52217.19 01.74 00.20 average of 69 hours outside of the classroom on the cour- a 85 Students x 5 hours x 3 quarters = 1275 hours. se with verv little difference noted for class rank. Over b Estimated at 10.%5 hours per year or 43 hours per student.

NACTA Journal - June 1980 Table 6. Student Response by Class Rank to the Ques- agricultural disciplines, demand will increase for the tion "Compared to AD Other Courses You Have Taken course and for additional subject matter discus- at Ohio State How Would You Rank 'Computers in sion/laboratory sections. Agricultural Decisions' as to Its Utility in Preparing You For Your Future," Autumn Quarter 1979. References: Class Rank Aronofsky, Julius S., Robert J. Frame and Elbert B. Greynolds Jr. Rank 1 Sq&mures Juniors Seniors 1978. Programmable Calculators-Business Applicario~~s.New York. First 12 (12) 23 (23) 05 (05) 05 (05) NY: McGraw-Hill Book Company. Second 20 (32) 19 (42) 22 (27) I8 (23) Fuori, William M. 1977. Introducrio~lro the Computer-The Tool Third 35 (67) 27 (69) 13 (70) 36 (59) of'Business. Second Edition, Englenood Cliffs, NJ: Prentice-Hall, lnc. Fourth I l (78) 19 (88) 05 (75) 09 (68) Iowa State University Cooperative Extension S~MC~.1978. Fifth 8 (86104 (92) 17 (92)OS (73) Pmgramtnable CalcularorPr~grams Applied lo Agricultural De- LessThan 13 (100) 08 (100)08 (100) 27 (100) cisions. Ames, 1A: Iowa State University. Fifth McGrann, James M., and William M. Edwards. 1979. "Applica- tion of the Programmable Calculator to Extension Agricultural a Percentages are accurnulared in parentheses. Management Programs: Experience from Iowa." North Central Jour- 25 students. Small subject matter groups create good nal ~~'~~ric~tltural~conomics 1: 147-153. National Science Foundation. 1979. Technolog~lin Science Educcr- rapport between instructor and students and also among rion: The Next Ten Years. Perspectives and Reco~nnte~rdations. students. They also aid learning by allowing students Washington. 1979. more time to concentrate on areas of specialization. Northeast Regional Agricultural Engineering Service. 1978. Second, provide adequate equipment for almost Calcrrlator Programsfir Exre~lsion.Ithaca, NY: Cornell University. unlimited "hands-on experience." This can be ac- Shaffer, Richard A. 1979. "The Superchip-Vast Computing Power complished at relatively low cost by using programmable is Seen as More Circuits Squeeze on a Tiny Part." The Wull Streer Journal, LIX, No. 136. calculators. Third, anticipate and prepare for increased Texas Instruments, Incorporated. 1977. Pmgra~nrtlableTi-58159- demand for the course. As the need for this type of Solid State Softn.are Libraries and Other Accessories. Lubbock, TX: education is felt by students and educators in the various Texas Instruments, Incorporated.

Developing A Computer-Oriented Program Elisabeth N. Derbyshire and then to encourage and support those who wished to become involved. Action was concentrated in three areas: In the years leading up to 1974, the College of Agri- workshops. course work, and laboratory space. cultural Sciences at Colorado State University became The first thrust was a series of workshops and increasingly aware of the importance of the computer in seminars held in the spring of 1975. Since the Committee agriculture. Some faculty were, of course, using the com- felt it most important that these be conducted by a puter. but no centralized effort was being made to help faculty member whenever possible, an inventory of faculty and students assess the challenge, the opportunit- College computing usage was compiled and reviewed. ies, and the implications of this new tool. That year, as a The resulting seminar series included presentations on result of conversations between the Director of Resident test preparation, test grading, simulation, and op- Instruction in the College and the Director of the Univer- timization. These in turn generated interest in the FOR- sity Computer Center, the College made a formal com- TRAN programming language and, as a direct result, a mitment to computer-oriented agriculture. ten-week introductory FORTRAN workshop was held As a first step, a committee with representation the following fall. from each of the College's departments and the Com- In the area of course work, after much careful study puter Center was established and charged with advising the Committee recommended two new offerings. The first, the College on matters relating to computer utilization. A320 with no prerequisites, was for students with no Shortly thereafter, on the Committee's recommendation, computer background and had as its objective the iden- a member of the Computer Center staff was assigned to tification of the types of problems arising in agriculture the College on a joint appointment to assist faculty in the which are amenable to computer handling, including (a) use of the computer and to provide more effective com- simulation and optimization of problems in munication between the College and the Center. management, plant and animal processes, and mix for- From the beginning, the program operated on the mulation, and (b) data storage, retrieval, and analysis. philosophy that no staff member should be compelled to The second of the new courses. A420, had a program- use the computer. Rather, a climate was provided for ming course prerequisite and was for students whose faculty to examine a variety of computer applications commitment to agriculture was coupled with a natural in- terest and aptitude in computing. Such students had lit- Director of Computer Utilization, College of Agricultural Sciences, Colorado State Udversity, Fort Collins, CO 80523. tle opportunity to further their assimilation of computing NACTA Journal - June 1980