I. Read and translate the following text:

Microcomputers with 8, 12 or 16 - bit processors are all appropriate for process control. In addition to word length, users should also consider the following factors before deciding on a particular microcomputer: how easy is it to program? How flexible is it? Can the memory and input /output capability be expanded? And what is the system cost including memory, analog inputs, and power supplies? The size of the microcom­puter memory determines both cost and flexibility of the microcomputer - the larger the memory, the easier the microcomputer is to program, but also the more ex­pensive it is. Generally, microcomputers have two types of Semiconductor memory: random access memory (RAM) and Read-only memory (ROM).

RAM memory, sometimes called scratch pad memory, is used for temporary data storage during computations.

RAM memories are volatile - they lose their contents when power is lost, unless they have an uninterruptible power supply. Most microcomputers have 32 to 64 bytes or more (I byte = 8 bits) of RAM. Some smaller micro­computers do not have RAM since they perform no computations.

ROM memory stores the control program per­manently. One type of ROM memory, programmable ROM (PROM), can be programmed by the user in a separate development system and then plugged into the microcomputer. Eight-bit microcomputers generally have 512 bytes to IK or more of ROM.

Input and output devices connected to a micro­computer are virtually unlimited. The microcomputer in Fig. 1.for example, uses a keyboard for input and light emitting diode (LED) display for output. Since both are digital, some conversion devices are needed to convert incoming analog signals, and outgoing digital data. An analog-to-digital (A/D) converter converts the analog sensor data to digital data for the input and a digital-to-analog (D/A) converter converts the digital output to an analog signal to drive the actuator. Like a microcom­puter peripheral device, the converters can be con­nected to the address and data busses of the microcom­puter.

EXERCISES:

I. Answer the following questions:

1. What microcomputers are appropriate for process control?

2. Does the size of the microcomputer memory determine only cost of it?

3. How many types of semiconductor have microcom­puters?

4. What is RAM memory used for?

5. Why are RAM memories volatile?

6. Where can one type of ROM memory be programmed by user?

7. What can the converters be connected to?

IL Choose the Ukrainian equivalents from the right column:

Generally sometimes in addition to like a device along with such as

такий як. разом подібний крім того взагалі іноді

3. Define the terms using the word-combinations in brackets:

bit - (data, can, a unit,, system, in, binary, оr, that,take on, of, either, the value)

byte - (bits, that, a group, the compute-, of, perceives,as, unit, operates on, and, single)

4. Translate the following sentences into English:

1. Об'єм, пам'яті мiкрокoмп'ютера визначає ціну тагнучкість мікрокомп'ютера.

2. Чим більше пам'ять, тим легше комп'ютер має програмувати, але також він більш коштовний.

3. Пам'ятьRAM, яку іноді називають надоперативною, використовується для тимчасового збері­гання даних під час обчислення.

4. Пам'ять RAM непостійна - вона втрачає інфор­мацію, коли переривається постачання енергії.

5. Різноманітність пристроїв вводу та виводу, з'єдна­них з мікропроцесором, фактично безмежна,

LESSON 14.WHAT IS THE MODEM?

I. Read and memorize the following words:

electronic equipment- електронне обладнання . to transmit- передавати

to whistle- свистіти

to stick {stuck, stuck)- встромляти

tosnap- клацати "і

plug- штепсельна вилка

to avoid- уникати

above-mentioned-згаданий раніше

coupling-з'єднання

to render- робити

impaired- зіпсований

Weird- дивний

error-correction- виправлення помилок vendor- постачальник, фірма-виробник