Едеральное агентство по образованию кемеровский технологический институт пищевой промышленности

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Название	Едеральное агентство по образованию кемеровский технологический институт пищевой промышленности
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Тип	Учебное пособие

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SECTION II. SOFTWARE

LESSON SEVEN

Text A. The Basic Principles of Programming.

Text B. Programming.
Exercises

Read the international words and guess their meaning:

fundamental, principle, tactics, student, format, utilization, term, routine, actual, practice, list, planning, personal, to concentrate, personnel, detective, coding, programming, symbolic, final, procedure

Pronounce the following words correctly:

Introduce [,intrə'dju:s] v – вводить, знакомить, представлять

subroutine ['sлbru:'ti:n] п – подпрограмма, часть программы

entire [in'taiə] а – весь, целый, полный

routine [ru:'ti:n] п – (стандартная) программа

change [tƒeindʒ] n – перемена, изменение, v изменять

assign [ə'sain] v – назначать, присваивать

procedure [prə'si:dʒə] n – процедура, методика проведения (опыта)

debugging [di'bлgiη] n – наладка, отладка программы

error ['erə] n – ошибка, погрешность

invalidate [in'vælideit] v – выводить из строя

technique [tek'ni:k] n – метод, методика, технический прием define [di'fain] v – определять, формулировать (задачу)

diagram ['daiəgræm] п – диаграмма, схема, v строить диаграмму (схему)

flow-chart ['flou'tƒa:t] п – блок-схема, схема потока информации

shorthand ['ƒo:thænd] п – стенография, сокращенная запись

evidently ['evid(ə)ntli] adv – очевидно

precisely [pri'saisli] adv – точно

observation [,obzə(:)'veiƒ (ə)n] n – наблюдение, соблюдение

reemphasize ['ri'emfəsaiz] v – вновь подчеркнуть

erase [i'reiz] v – стирать (запись)

remain [ri'mein] v – оставаться

replace[ri'pleis] v – заменять, подставлять, перемещать

3. Memorize the following word combinations:
a computer manual – руководство к компьютеру

it should be pointed out – следует указать

commercially available computers – серийно выпускаемые компьютеры

complete list of – полный список (перечень)

over-all planning – общее планирование

so-called – так называемый

actual coding – действительное кодирование

debugging the code – отладка кода

running the code on the computer – прогон кода на компьютере

a single error – единственная ошибка

the rest of the bits – оставшиеся биты

octal numbers – восьмеричные числа

previous contents – предыдущее содержание

TEXT A

THE BASIC PRINCIPLES OF PROGRAMMING

1. Introduction. The purpose of this chapter is to introduce the student to the fundamental principles of coding and programming. These principles are connected with the stages of programming, the flow-charting using the subroutines and the computer manual, etc. In order to leave students free to concentrate on these principles, the four-address format with a minimum of instruction types is utilized. However, it should be pointed out that the four-address format is used in this chapter for pedagogical reasons only. In practice commercially available computers use only three-, two- or one-address formats, the latter perhaps being the most common.

2. The Terms 'Coding' and 'Programming' are often used as synonyms. However, 'a code' is more specifically a short list of instructions that direct the computer to perform only a part of the entire calculations, whereas the term 'program' refers to the complete list of instructions used for the problem. Hence the term 'programming' usually includes the over-all planning of the use of the computer for a particular problem as well as the writing of the instruction lists or codes, whereas 'coding' is usually limited in meaning to the writing of the instruction lists. Sometimes a code is called a routine.

3. Stages in Programming. There are five stages in programming. First, the computations to be performed must be clearly and precisely defined. The over-all plan of the computations is diagrammed by means of a so-called flow chart. The second stage is the actual coding. It is often best to write a code in terms of a symbolic language first, for then changes are easily made. Numbers are assigned to the symbols, and the final code is prepared. In the third stage some procedure is used to get the code into the memory of the computer. The fourth stage consists of debugging the code, i.e., detecting and correcting any errors. The fifth and final stage involves running the code on the computer and tabulating the results. In fact, it is well known that a single error in one instruction invalidates the entire code. Hence, programming is a technique requiring attention to details without loosing sight of the over-all plan.

4. Instruction Format. Some bits of the instruction are set aside for the operation code designation — i.e., they tell the instruction is 'add', 'multiply', 'divide', etc. The rest of the bits usually define the four addresses. For the more usual operations that involve two operands, such as addition, multiplication, etc., two of the addresses are the addresses of operands. The third address tells where the result is to be put; the fourth address tells where to obtain the next instruction. So, the instruction format is the way in which the different digits are allocated to represent specific functions.

5. Octal Shorthand. The first important detail of coding is the fact that the actual bits in an instruction are not written out in the binary code; rather, some shorthand is written instead, i.e., the octal equivalent would be written out. In other words, two octal numbers represent the instruction, and each address would be represented by three octal numbers. Thus, if 101 011 is the binary code for the command 'add' then the instruction that says, "Add the contents of address 011 010 110 to the contents of address 011 100 101, put the result into address 011 110 100, and take the next instruction from address 100000001," is written in octal notation as: operation – 53, the first operand address – 326, the second operand address – 345, the third address – 364, and the fifth address – 401. In such cases it evidently facilitates matters to call addresses in the memory by their octal numbers. Also, numerical quantities will be written on the code sheet in octal (i.e., they will have to be converted from decimal to octal before being written on the code sheet).

6. The Computer Manual. For the computer we must have a computer manual that gives the operation codes of different instructions and also defines precisely the meaning of the addresses for each instruction type. The coding manual must always be at the coder’s side. Two further observations must be reemphasized: first, when a word is called into the arithmetic/logic unit from the memory, it is not erased from its memory address but remains there also; second, when a word is put into a memory address, it replaces the previous contents of this address, i.e., it erases what has been there.

(To be continued)
Notes:

in order to leave students free to concentrate on these principles – чтобы дать возможность студентам сосредоточиться на этих принципах

without losing sight of – не теряя из виду

are set aside for the operation code designation – откладываются для обозначения кода операции

It evidently facilitates matters – это, очевидно, облегчает дело (ситуацию)

must always be at the coder's side – должен всегда быть у программиста под рукой

Exercises
4. Find the Russian equivalents to the following English words and word combinations:

1.then	1. точно
2. thus	2. легко
3. hence	3. ясно
4. however	4. вместо чего-либо
5. whereas 6. perhaps 7. also 8. sometimes 9. there 10.in other words	5. кроме того 6. вероятно 7. также 8. следовательно 9. однако 10. затем
11. moreover 12. instead of 13. the current chapter 14. in fact 15. specifically 16. often 17. in addition to 18. easily 19. clearly 20. precisely	11. таким образом 12. иногда 13. там 14. более того 15. другими словами 16. в действительности 17. часто 18. данная (текущая) глава 19. тогда как 20. специфично, специально

5. Memorize the following definitions:
1. A program is a set of instructions composed for solving a given problem by a computer. 2. A code is the representation of data or instruction in the symbolic form. 3. A procedure is the sequence of steps required to solve a problem. 4. Programming is the process by which a set of instructions is produced for a computer to make it perform specified activity.

6. Answer the following questions:
1. What is a code? 2. What is a program? 3. What does the term 'programming' include? 4. How many stages are there in programming? 5. Which are the stages in programming? 6. What does programming require? 7. What will happen if there is a single error in one instruction? 8. What does the computer manual give and define? 9. When does a word erase the previous contents of the memory address? 10. When isn’t a word erased from its memory address? 11. What are some bits of the instruction set aside for? 12. What is an instruction format? 13. Why are the octal code often used instead of the binary code?
7. Read and translate the following sentences paying attention to the meaning of the words and word combinations given below:
a) a number – число, количество; номер

to number – насчитывать

a number of – ряд, множество

1. This professor's lectures on microprocessors and microprogramming are attended by a great number of students. 2. The students' body of our automation department numbers more than 500 students. 3. The first automatic digital computer could add numbers at the speed of 5000 additions per second. 4. The address of our Institute is the Prosveschenya Street, number 132. 5. A number of computing devices were arranged in our laboratory.
b) mean – средний, среднее число

means – средство

to mean – значить, означать

meaning – значение

by means of – посредством

by no means – ни в коем случае

1. The year mean temperature in our town is about +8°C. 2. Electrical typewriters and keyboard devices are the common means of input into a computer. 3. This means that the ROM is the permanent memory chip for program storage. 4. By means of arranging memory registers inside hardware it is possible to store information and instructions. 5. By no means the computer can substitute a human being in all respects. 6. The meaning of the word “means” is «средство», «состояние».
c) term – термин, срок, семестр

to term – называть

in terms of – с точки зрения, на языке, в терминах

1. The term "programming" means the process by which a set of instructions is produced for a computer to make it performing specified activity. 2. President of the USA is elected for a four-year term. 3. Each academic year at institutes and universities in our country consists of two terms. 4. A code can be written in terms of automatic language in order to make easy changes in it. 5. A code may be termed a program or a routine because they are synonyms. 6. If the language described is called simply "the language", then the language in terms of which the description is being made is called "metalanguage".
d) available – доступный, имеющийся в наличии, пригодный

1. A number of different computing devices available in our Institute's lab is very great. 2. The computer ES-1045 is now available for students' use. 3. Of all the instruments available the control generator is the most suitable for producing electrical impulses.
e) any – любой, всякий (в повествовательных предложениях)

I. Any operation performed by a computer must be interpreted into a machine code. 2. Any sort of likeness to a human being is simply irrational while constructing robots.
f) rather – довольно

rather than – скорее чем, предпочтительнее

1. It would be rather difficult to predict the place where the moon will be at any particular time without computers. 2. The instructions deal directly with addresses rather than with the numbers themselves.
g) instead – вместо, взамен

instead of – вместо, взамен

1. Boolean Algebra is algebra like ordinary one but dealing instead with classes, propositions on-off circuit elements, etc. 2. In digital computers octal notation (восьмеричное счисление) is sometimes used instead of binary numbers.
8. Read Text В and write a brief summary of it:

TEXT B

PROGRAMMING

The word 'program' has come into use to refer to the sequence of instructions that a computer carries out. A program for a computer is an exact sequence of instructions that it uses to solve a problem. It usually consists of subroutines or subprograms, which are portions of it.

Programming for automatic computer requires a good deal of knowledge, common sense and training. Specially, programming requires: (1) understanding the operations of a business or the steps of a scientific calculation; (2) understanding the best way for having a computer carry out these operations and steps; (3) arriving at a good sequence of commands for the computer to solve the problem; and (4) adequately translating these commands into the computer language.

Programming for the computers has several forms. One form is the construction of compiling programs or compilers — which use the computer to take subprograms out of a library and link them together appropriately so as to solve a new problem. A second form is the construction of programs called interpreters, which accept instructions in certain standard words and translate these words into a machine language, so that the machine "knows" what the words "mean". A third form is the development of common languages for automatic programming for problems, so that any problem when expressed in such a language can be given to any automatic computer and the computer will translate the common language into its own instruction code, and then solve the problem.
9. Translate the following dialogue from Russian into English:
В ВЫЧИСЛИТЕЛЬНОМ ЦЕНТРЕ

НАШЕГО ИНСТИТУТА
Студент: Здравствуйте. Я хотел бы видеть оператора.

Оператор: Я оператор. Чем могу быть полезен вам?

Ст.: Видите ли, мне хотелось бы задать вам несколько вопросов относительно устройства и работы вычислительной машины.

Оп.: С большим удовольствием отвечу вам. Пойдемте. Вот электронный компьютер ЕС-1045. Он является представителем семейства компьютеров, входящих в Единую Систему (the Unifed System of Computers). Его быстродействие – 880000 операций в секунду, а объем ОЗУ – оперативного запоминающего устройства (the main memory capacity) – равен четырем мегабайтам (4 MB).

Ст.: А что значит Единая Система ЭВМ?

Оп. Единая Система ЭВМ – это такая система, которая использует программно-совместимые модели (program-compatible models), предназначенные для решения широкого круга научно-технических и экономических задач. В ЭВМ ЕС применяются большие интегральные схемы (LSI circuits).

Ст.: А что собой представляли компьютеры второго поколения? Каково было их быстродействие, вместимость памяти?

Оп.: Компьютеры второго поколения строились на полупроводниках (solid-state computers). Их ОЗУ строились на магнитных ферритовых сердечниках (the magnetic ferrit cores), а ПЗУ — постоянное запоминающее устройство (the read-only memory) — на магнитных лентах. Объем ОЗУ был около 70000 – 100000 байт. Их быстродействие было от 30000 до 50000 операций в секунду. Обращение к памяти (the access time) составляло 5 – 7 микросекунд. Машины второго поколения уже устарели (has become obsolete). Компьютеры 3-го и 4-го поколений считают в сотни и тысячи раз быстрее.

Ст.: А это какой компьютер?

Оп.: Это микрокомпьютер «Искра-1256». Объем его ОЗУ 64 KB. Он построен на БИСах (LSI circuits). А это алфавитно-цифровое печатающее устройство (the alphanumerical printer).

Ст.: Большое спасибо. Разрешите мне прийти еще раз.

Оп.: Пожалуйста. Я расскажу вам об устройстве машин 4-го поколения, например, о компьютере «Наири-4», быстродействие которого увеличилось по сравнению с компьютерами 3-го поколения в 5 раз, благодаря применению многослойных печатных схем ( multilayer printed circuits).

Ст.: С удовольствием приду. До свидания!