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TEXAS INSTRUMENTS: SR60A


The SR60(A)'s business capability ranges from solving intricate financial analyses and long-range forecasting, to simpler operations like payroll and amortization. The unique 20-character display lets the user run alphanumeric programs which 'ask' for information at successive stages of the problem. The machinbe then waits for a user response before continuing. This dialogue allows even a novice to work with complicated problems immediately. Programming is quite easy and straightforward yet flexible for the user. By using the printer users can list and trace the actual program execution. Programs are written and recorded on magnetic cards. With alphanumeric prompting, the cards can be used by assistants or secretaries. A person generally needs a minimum amount of instruction and a general concept of what's to be solved to have answers in seconds. The preordered cards are included in the SR60(A) Basic Library: Power transformer and filter design. Add-on rate installment loans and compound interest. Polynomial evaluation, cubic and quadratic equations. Basic statistics. Random number generator and diagnostics, etc. Well over 100 optional additional programs are available, including many on business. The SR60(A)'s quiet printer provides a scaled replica of what appears on the alphanumeric display on 2 1/2-inch thermal paper. Users can get a hard copy of any keyboard calculation that appears on the display, a complete program list of the contents of the data registers, whether entered from the keyboard or from a program card. A Novice Helper: Feature: Desktop Programmable Calculator Prompts Users: The SR60(A)'s programmable desktop calculator features a display that communicates with the user. It includes a printer, magnetic card reader and additional function keys. With its 'prompting'-display, an SR60(A) user can run alphanumeric programs which request information through the 20-character display at successive stages in a problem. The calculator then waits for a response before continuing with problem solving. The SR60(A) is designed for both business and technical operations. For future development, the SR60(A) is designed to accommodate I/O peripherals, which would expand its capability in data storage and variety of readout. Each printed char character is also in a 5 x 7 dot matrix. Through the printer, the user can record results of keyboard calu1ations, any displayed item, complete program listings of data register contents, and a printed trace of the execution of the problem, whether entered from the keyboard or run with a program. The unit has 95 keys, including 40 for mathematical functions, 46 for scientific functions, and the rest mostly for instructions. The unit can also be operated as a ‘general purpose’-calculator. It has left-to-right algebraic entry and nine levels of parentheses to allow users to enter problems as they normally would say them. At the users' option, answers can be displayed, printed out on a dot-matrix thermal printer, or both. Some users suggest that the TI calculator is generally comparable in performance HP’s: 9815A or CANON’s: SX310. TI originally shipped the SR-60 with 10 basic program cards. An additional 100 cards, designed for specific technical and business applications, were available priced from $95.00 each. TI was able to hold down the SR60(A)'s manufacturing cost (and its price) by making almost everything in the unit, including the case. Two diagnostic programs are also supplied to test the SR60(A)'s internal operation. Users also get a Basic Library Manual which details each program, contains sample problems, user-instructions and program listings. The SR60(A) Basic Library offers a basic variety of mathematical programs. Programs that will add to user problem-solving capability: Six libraries containing well over 100 different programs are available. Finance, with 21 programs and Electrical Engineering with 16 programs were available first. The others: Math I, 20 programs. Math II, 18 programs. Statistics: 19 programs, and Surveying: 7 programs. Here is a sampling of the kinds of problems the SR60(A) can be programmed to handle: Business, Profit and loss statements, Balance Sheets, Payroll, Trend lines, Economical ordering, Depreciation schedules, Crossover between straight line and declining balance, Loan amortization, Discounted cash flow, Simple and compound interest, Rule of 78's, Annuities, Days between dates, Date conversion, Bond yield. Technology/Science: Evaluate complex functions, Evaluate polynomials with complex coefficients, Find real and complex roots of cubic and quadratic equations, Solve transcendental equations, Approximate integrals, Find approximate solutions of differential equations, Assist in power transformer design, Assists in filter design, Performance of many statistical calculations. SR60(A) Prompting: The alphanumeric prompting feature used in conjunction with programming, displays letters, numbers and special symbols that let users make words and phrases that will later 'ask' for entries or decisions to solve the problem. The large (1 1/4 by 9 1/4 inch) 20-character light emitting diode display (5 by 7 dot matrix) 'asks' users for their input, in terms they understand, at each stage of the problem, then waits for their keyed in response before it continues. So users really interact or 'talk' through" a problem — Users providing raw data, the SR60(A) giving back complete answers. This rapid dialogue lets users solve a problem using different inputs, letting them explore multiple options. And, should the dialogue be interrupted, users leave the SR60(A) on and its display will tell them where they are when they return. As long as the user gives the appropriate input to each question, he doesn't need to know how to ‘solve’ the problem, the machine does it automatically. Any program can be recorded on blank magnetic cards for continued use. Algebraic operating system (AOS) with 9 levels of parentheses solves problems with up to 10 pending operations. Entry is left-to-right just as the problem is written. Results are displayed up to 10 digits, plus two more for power of 10 exponents. The trace mode key automatically begins recording all calculations whether entered from the keyboard or run with a program. So users can see how the program is being executed. This is very useful for editing and debugging a program. It conveniently lets users verify that instructions are keyed in correctly and get a quick check on hastily constructed programs, or programs not carefully documented. Users verify that program results are based on correctly formulated problems. SR-60(A) Keys and Programming Procedure: Programming is really no more than taking small problems and integrating them to solve bigger problems. On the SR60(A) programming is merely listing the keystrokes necessary to carry the problem through to its solution. Some may still feel that programming is too complex for the untrained person to master. A view that probably is helped along by the vocabulary associated with programming. Words like direct and indirect addressing, conditional and unconditional branching, labels, and flags sound esoteric and abstract. Yet these words are just a shorthand use to describe manipulations almost anyone can grasp. In fact, they're not even mathematical. Even though the machine has many functions, no one can anticipate all their needs. Fifteen user-defined keys are provided to make them any function users may need. The Label key tells the SR60(A) that the next key pressed will be a label. There are 77 keys, including the user-defined keys, that can be used as labels. If Positive, If Zero, and If Error are keys that test the contents of the display. Branching occurs if the conditions: positive, zero, or flashing display are true. Branching occurs if the conditions are not true when these keys are prefixed by the 2nd key. Alternate calculating paths can be defined by the Set Flag key followed by a number from 0 through 9 then the Test Flag key tests the state of the flag- set or reset. The SR60(A) branches if the specified flag is set, or continues sequentially if the flag is not set. 2nd, Test Flag reverses the sense of the test. The indirect addressing (IND) key is used with unconditional, conditional and data memory keys. An example: IND, TFLG, 2,05. means that SR60(A) tests flag number 2, and looks at the contents of the data memory register 05 to find the program address to which to branch if flag 2 is set. The Que key halts the SR60(A)'s operation and waits for a response from these keys: Yes, No, Not Known, Not Apply, Enter. Press Yes and the SR-60 branches to the first label which follows Que. Pressing No causes it to branch to the second label, and so on. These five label keys are equivalent to a five-way branch. The alphabetical letters and symbols on keys are activated by the Alpha key to enter prompting messages for display or print. The convenient Pause key permits a message or result to be displayed for about 1/2 second. The SR-60's editing and debugging keys let users go through a program one step at a time. Or single-step backward through a program. The Insert key moves the current and all following instructions down one location so that a change can be made at any place within a program without rewriting it. Users remove the displayed instruction and move all following instructions up with the Delete key. The machine can print a trace, or a record, of all functions, numbers, and calculations record, of all functions, numbers and calculations.