Peripheral equipment

Flash memory is a non-volatile computer storage that can be electrically erased and reprogrammed. It is a technology that is primarily used in memory cards and USB flash drives for general storage and transfer of data between computers and other digital products. It is a specific type of EEPROM (Electrically Erasable Programmable Read-Only Memory) that is erased and programmed in large blocks. In early flash memory the entire chip had to be erased at once.

Flash memory costs far less than byte-programmable EEPROM and therefore has become the dominant technology. Example applications include PDAs (personal digital assistants), laptop computers, digital audio players, digital cameras and mobile phones.

Since flash memory is non-volatile, no power is needed to maintain the information stored in the chip. In addition, flash memory offers fast read access (although not as fast as volatile DRAM memory used for main memory in PCs) and better kinetic shock resistance than hard disks. These characteristics explain the popularity of flash memory in portable devices. Another feature of flash memory is that when packaged in a "memory card," it is enormously durable, being able to withstand intense pressure, extremes of temperature, and even immersion in water.

Flash memory (both NOR and NAND types) was invented by Dr. F. Masuoka while working for Toshiba in 1980. He presented his invention at the International Electron Devices Meeting held in San Francisco, California in 1984. Intel Corporation saw the massive potential of the invention and introduced the first commercial NOR type flash chip in 1988. NOR-based flash was the basis of early flash-based removable media; CompactFlash was originally based on it, though later cards moved to less expensive NAND flash which was announced by Toshiba at the International Electron Devices Meeting in 1987. NAND flash is similar to other secondary storage devices such as hard disks and optical media, and is thus very suitable for use in mass-storage devices such as memory cards. The first NAND-based removable media format was SmartMedia, and many others have followed, including MultiMediaCard, Secure Digital, Memory Stick and xD-Picture Card. A new generation of memory card formats, including RS-MMC, miniSD and microSD, and Intelligent Stick, feature extremely small form factors. For example, the microSD card has an area of just over 1.5 cm², with a thickness of less than 1 mm; microSD capacities range from 64 MB to 16 GB, as of August 2009.

TASKS

1. Give Russian equivalents of the following words and word combinations. Transcribe them.

1. volatile (adj.)

2. erase (v.)

3. technology (n.)

4. primarily (adv.)

5. entire (adj.)

6. maintain (v.)

7. characteristics (n.)

8. enormous (adj.)

9. durable (adj.)

10. pressure (n.)

11. commercial (adj.)

2. Give English equivalents of the following words and word combinations

3. Translate the groups of words. Mind: the prefix –non has a negative meaning.

1. productive (adj.) – non- productive (adj.)

2. volatile (adj.) – non-volatile (adj.)

3. programmable (adj.) – non- programmable (adj.)

4. resistant (adj.) –non-resistant (adj.)

4. Translate the following word combinations into Russian and formulate the rule of the meaning of the prefix -re.

1. to read the instructions – to reread the instructions

2. to write a program –to rewrite a program

3. to wind the wire – to rewind the wire

4. programmed device – reprogrammed device

5. constructed computer – reconstructed computer

6. counted objects – re-counted objects

5. The word “that” used in complex sentences may be translated as «который» and «что». Write out the sentences in which the word “that” is translated as: a) «который», b) «что».

1. Flash memory is a non-volatile computer storage that can be electrically erased and reprogrammed.

2. It is a technology that is primarily used in memory cards and USB flash drives for general storage and transfer of data between computers and other digital products.

3. It is a specific type of EEPROM (Electrically Erasable Programmable Read-Only Memory) that is erased and programmed in large blocks.

4. Another feature of flash memory is that when packaged in a "memory card," it is enormously durable, being able to withstand intense pressure, extremes of temperature, and even immersion in water.

6. Read and translate the text.

Peripheral equipment

The microcomputer has to communicate with the outside world, so that programs and data can be entered into its memory and processed information can be displayed or transmitted in some form to the microprocessor user.

There are various types of peripheral equipment that may be attached to microcomputers including keyboards, visual display units (VDUs), magnetic recording devices, and printers for output.

Different sensors and actuators may be linked (interfaced) to the microcomputer for controlling instruments and machines.

Keyboards

A keyboard consists of a number of switches which are activated by pressure or simply by touching them. The layout of the keyboard may be similar to that of the typewriter or may be designed for particular users. For example, if a large amount of the numeric data to be entered, then key pad may contain keys for decimal 0 through 9, and some special characters.

Visual display units

These units have a cathode-ray tube (CRT) for displaying information and often a keyboard which may be attached or is detachable. The VDU may be part of a self-contained microcomputer, with all the necessary circuitry contained in the case holding the CRT.

The output from the keyboard is decoded into a form suitable for the computer being used. This function is usually carried out within the VDU which may also have its own buffer, so that information keyed in is not transmitted immediately giving the operator a chance to correct it.

Other more sophisticated features may be available on more expensive VDUs such as graphics facilities and screen-editing. With the latter facility, changes may be made to information displayed on the screen by moving a special character (cursor) to the position on the screen which requires alteration. Often these facilities will be under the control of programs stored in ROMs on the VDU board. Additionally, a light pen may be used as an input device by pointing it to the required on the screen.

Magnetic recording devices

Magnetic disks have data recorded on them in a series of circular tracks. Each track is divided into sectors and is uniquely identified. Data is transferred in sectors or groups of these. Read/write heads are moved to the appropriate track for recording or accessing data under hardware/software control, so that random access of data can be achieved. Indexes may be used to enable the required data to be located or data may be retrieved randomly by using relative addressing, in which data is recorded in known positions. Data may also be recorded serially as on magnetic tape.

Hard disk is the most reliable recording device. Hard disk drives, available for use with microcomputers, are usually based on Winchester technology. The units consist of a hard disk totally enclosed and sealed in a chamber. This ensures that extraneous particles of dust or dirt cannot get into the very small gap between the fast spinning disk and the floating read/write head, as this would cause a head-crash which would ruin the head and disk resulting in the loss of all the information held on the disk.

Printers

Printers are used to spell out the information needed. Advances in technology have allowed rapid printers to be developed. Laser printers, for example, are capable of printing miles of documents without stopping. This high productivity makes laser printers ideal for large-volume printing.

TASKS

1. Transcribe and give equivalents of the following words:

1. keyboard (n.)

2. visual (adj.)

3. sensor (n.)

4. actuator (n.)

5. switch (n.)

6. pressure (n.)

7. decimal (adj.)

8. character (n.)

9. cathode (n.)

10. tube (n.)

11. detachable (adj.)

12. circuitry (n.)

13. suitable (adj.)

14. immediately (adv.)

15. facility (n.)

16. cursor (n.)

17. alteration (n.)

18. circular (adj.)

19. appropriate (adj.)

20. extraneous (adj.)

2. Give equivalents of the following word combinations:

1. microprocessor user

2. visual display units (VDUs)

3. magnetic recording devices

4. the layout of the keyboard

5. numeric data

6. key pad

7. cathode-ray tube (CRT)

8. self-contained microcomputer

9. graphics facilities

10. screen-editing

11. VDU board

12. light pen

13. circular tracks

14. read/write heads

15. random access

16. relative addressing

17. magnetic tape

18. hard disk

19. hard disk drives

20. Winchester technology

21. fast spinning disk

22. floating read/write head

23. laser printer

Date: 2015-01-02; view: 1208