“Option 1 For long-term storage of information is used: RAM; external memory; drive; CPU. In the operating system ... "

Option 1

rAM;

external memory;

drive;

cPU.

question mark (?)

file creation time;

file size;

where the file was created.

A spreadsheet is:

application program for processing code tables;

application program for processing data structured in the form of a table;

a computer device that manages its resources when processing tabular data;

a system program that manages computer resources when processing tables.

The driver is

long-term storage device

program that controls a specific external device

input device

output device

How much information does the message contain that one of the 16 students in the group is the winner of the computer science Olympiad?

1024 bytes.

MARK THE CORRECT ANSWER

Mysterious Brain Rescue

Master Boot Record

437451552070 Answer:

A) 12; B) 16; C) 8; D) 10

A) 12; B) 16; C) 8; D) 10

A) 43; B) 61; C) 49; D) 56

Option 2

The main element base of the first generation computers are:

semiconductors;

electromechanical circuits;

very large integrated circuits;

electric vacuum lamps.

In which PC device is information processing performed?

external memory

cPU

The device for inputting information from a sheet of paper is called:

For long-term storage of information is used:

rAM;

external memory;

drive;

cPU.

On Windows operating system, the proper filename cannot contain the character

question mark (?)

comma (,) period (.) addition sign (+) A file name extension, as a rule, characterizes:

the type of information contained in the file;

file creation time;

file size;

where the file was created.

MARK THE CORRECT ANSWER

7. What do these pictures have in common?

A) logos of popular browsers

B) operating system logos

C) graphic editor logos

D) text editor logos

8. Mark the format of the vector drawing.

A) * gif; B) * cdr; C) * jpeg; D) * png9. Information capacity is ...

the maximum possible amount of data that this memory device can store

time interval from the moment of sending the request for information to the moment of receiving the result on the data bus

the amount of data transmitted per unit of time after the immediate start of the read operation (i.e., excluding the preparatory stage)

10. Which of the following programs is anti-virus?

A) Konqueror; B) Nero; C) Avira; D) FineReader11. What data type is char in Pascal?

AND). Logical; AT). Whole; FROM). Symbolic; D). Enumerable

12. What is NOT related to input devices?

A) touch panel; B) scanner; C) microphone; D) plotter

13. What does MBR stand for?

Mysterious Brain Rescue

Master Boot Record

Main Basic ReloadMinimal Be Restructure

4787900335915Select an answer:

A) 12; B) 16; C) 8; D) 10

00Select answer:

A) 12; B) 16; C) 8; D) 10

14. In the algorithm written below, integer variables k and m are used. Determine the value of the variable m after executing this algorithm:

15. What is the name of the science of methods of ensuring confidentiality, data integrity (the impossibility of imperceptible changes to information), authentication (verification of the authenticity of authorship or other properties of an object), as well as the impossibility of rejection of authorship?

A) kryptonics; B) cryptography; C) cryptanalysis; D) cryptology 16. Determine the required video memory for graphics mode with a resolution of 1024x768 pixels and a color depth of 16 bits.

A) 1,574 KB; B) 1,536 bytes; C) 1 536 KB; D) 1,574 MB

17. Extensions * aifc, * aac, * ogg have:

A) video files; B) graphic files; C) audio files; D) text files

18. Only cars and motorcycles are in the parking lot. There were 50 vehicles in the parking lot, of which 32 were cars and 15 were motorcycles. After that 11 more cars arrived. How many vehicles are in the parking lot in decimal notation?

A) 43; B) 61; C) 49; D) 56

1. THEORETICAL QUESTIONS ON SECTIONS AND TOPICS

2 semester 1 course

Computer presentations. Basic requirements when creating a presentation

What parameters are selected simultaneously for all slides in the presentation

What parameters are selected individually for each slide of the presentation

Why do you need design in presentations? How to choose a background for a slide

What determines the layout of the slide. What layouts are used more often.

What is the difference between animation and sound in the PROCESS OF CHANGING SLIDES from animation and sound in the PROCESS OF APPEARANCE OF OBJECTS on a slide?

How can you organize transitions between slides in an interactive presentation

Appointment of text editors. List what text editors are used in working with documents.

What operation in a text editor provides automatic search and replacement of words throughout the document.

What color is the spelling error in the text, and what is the syntactic

What needs to be set before printing a document

What is the main object in the text. What is a font What fonts differ in the way they are presented on a computer

Which fonts are easier to see with the eye. What is the unit of measure for font size

What types of data can be stored in cells of an Excel spreadsheet. Advantages of Excel spreadsheets over regular tables .. What determines the cell address in the spreadsheet. What cannot be deleted in an Excel spreadsheet.

What caused the creation of computer networks. What networks present to users

LOCAL networks. TOPOLOGY OF NETWORKS

What is a server-based network

WITH THE HELP OF WHAT the computers are connected

GLOBAL computer network INTERNET, THEIR CLASSIFICATION

This ensures the reliability and stability of the GLOBAL computer network. What is an IP address

What Internet Service Providers Provide. List the WAYS of connecting to the Internet. What determines the real speed of the Internet connection.

Answers to tasks

Question number

Option 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Option 1 B A A B B C D B A C C D B A B C C A

Option 2 D C C B A A D B A C C D B A B C C A

Similar works:

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"An example of the act of implementation in production" APPROVED "General Director of JSC" BelVTI "A.V. Kirpichnik _._. 2013 M.P. I approve the Vice-Rector for Academic Affairs and Social Affairs of BSUIR _ A.A. Khmyl _._. 2013 MP ACT OF IMPLEMENTATION (USE) of the results of scientific research ... "

The means of long-term storage and accumulation of data (external storage device) provide recording and reading of large amounts of information, which can be used as: program texts in high-level languages, programs in machine codes, data files, etc. As external storage devices in a PC, floppy disk drives (floppy disk drives) and hard disk drives (HDD) of the "hard drive" type are mainly used.

Floppy disk drives are the main external memory devices of a PC. The information carrier in the floppy disk drive is a flexible magnetic disk (HMD) made of a synthetic film coated with wear-resistant ferrolacquer. Information on the KMT is placed in a sequential code on concentric circles (tracks), each of which is divided into sectors. The sector is a unit of data exchange between the OP and the NGMD. One sector can hold 128,256, 512 or 1024 bytes of data. In a PC, the listed data formats can be installed programmatically.

HMD has a locating hole (UO) for fixing the disc in the drive and an index hole (IO) for identifying the beginning of tracks. To protect against the adverse effects of the external environment, the HMD is placed in a rectangular envelope with a slot for the supply of magnetic heads (PMG), a slot for the index hole (FIA) and a hole for attaching the HMD in the drive (OKD). The information that is recorded on the KMT, according to its purpose, is divided into service and work. Service information is used to control and synchronize the operation of the floppy disk drive. It, in turn, is subdivided into information that identifies the track and information that identifies the sector. Operational information represents user data.

The capacity of the floppy disk drive in the PC is 160 KB and more, depending on the number of magnetic heads in the drive and the density of data recording on the disk drive. There are the following types of floppy disk drives: with single and double recording density; one-sided - with one and double-sided - with two MG. In double-sided floppy drives, both surfaces of the GMI can be used to write and read data. In accordance with the types of floppy disk drives, the corresponding marking of the GMD was also adopted: SS - one-sided single-density disc; SD - double density single sided disc; DD is a double-sided disc of double density.

Along with the floppy disk drive, the developed PC models are also equipped with hard drives on magnetic disks of the "hard drive" type. Their distinctive features are a hermetically sealed single design of the disk, magnetic read-write heads and their drives, a small gap (compared to conventional UDM) between the magnetic heads and the disk surface (0.5 μm), a small pressure of the magnetic head (10 g compared to 350 g in conventional LMD), small thickness of the magnetic disk.

The hermetically sealed design doubles the reliability of operation as compared to conventional LMD. Reducing the gap between the disk surface and the magnetic heads significantly increases the longitudinal and transverse recording density. LMDs of the "Winchester" type are considered the third generation of LMDs and have characteristics that are close to the limit. So, an NMD with a diameter of 356 mm on one surface can include up to 1770 tracks (1300 MB of information).

Development of modems.

The first information processing systems, in which telegraph equipment was used to connect subscribers to computers, were created in the early 60s. In such systems, transmission was carried out using conventional telegraph equipment at relatively low rates, not exceeding 110 bits / sec.

The next stage in the development of data transmission systems was the development of modems that provide the ability to transfer binary information over telephone lines.

Modem- an electronic device equipped with the functions of modulating data at the transmitting end of the communication line and demodulating at the receiving end of the communication line. Modulating a signal means converting a signal to a form that allows it to be transmitted over long distances. For example, a typical acoustic modem is equipped with two cup-shaped receptors on which a telephone receiver is placed. The modem is connected to a computer, from which it receives information in the form of a sequence of binary signals - bits. However, the telephone is designed to transmit audio frequency, and the binary bits are just electrical impulses that cannot be heard by the human ear. Therefore, electrical impulses are pre-converted in the modem into audio signals, and then transmitted over telephone lines. At the other end, the reverse process of converting audio signals into a sequence of binary electrical impulses - bits suitable for the operation of a computer - takes place. Such transformations are called modulation and demodulation, the described device is just the simplest modem.

The first samples of modems had a relatively low data transfer rate, but later the transfer rate over switched channels increased to 1200 bit / s in duplex mode - the mode of simultaneous input and output of information, or up to 9600 bit / s in half-duplex mode - a mode designed for alternate input and information output.

In the mid-60s, the intensive development of specialized information processing systems based on dedicated channels began. Such systems are created to meet the needs of individual organizations that own both computing resources and communication channels. However, the operation of such systems has shown that the computing resources and communication channels used in them are not used effectively enough, the systems turn out to be expensive and poorly adapted to changing conditions. The need for many users to access powerful computers for relatively short periods of time has emerged.

All this led to the development of shared data transmission systems, in which many users can connect through public communication networks of their choice to various information processing facilities.

Keyboard.

The keyboard is an important and versatile device for entering information into a computer.

According to the arrangement of the keys, desktop keyboards are divided into two main types, functionally not inferior to each other. In the first version, the function keys are located in two vertical rows, and there are no separate groups of cursor control keys. There are 84 keys in such a keyboard.

The second version of the keyboard, which is commonly called improved, has 101 or 102 keys. Almost all desktop personal computers are equipped with this type of keyboard today. Professionals do not like this keyboard due to the fact that the function keys have to reach far, to the topmost row of keys across the entire letter keyboard. However, the number of function keys in the improved keyboard is not 10, but all 12.

In a laptop computer, the keyboard is usually an integral part of the design.

The location of the letter keys on computer keyboards is standard. Today, the QWERTY standard is widely used - for the first six Latin letter keys of the top row. It corresponds to the domestic standard YTsUKEN of the arrangement of the Cyrillic keys, which is practically similar to the arrangement of the keys on a typewriter.

Standardization in the size and position of the keys is needed so that the user on any keyboard can work in a “blind way” without retraining. The ten-finger blind method is the most productive, professional and efficient. Alas, the keyboard, due to low user productivity, is today the bottleneck of a high-speed computing system.

Working with the keyboard is very simple and intuitive. In order to assign a certain byte of information to each character on the keyboard, a special table of ASCII codes (American Standard Code for Information Interchange) is used, the American standard for codes for the exchange of information used on most computers.

When a key is pressed, the keyboard sends an interrupt signal to the processor and causes the processor to suspend and switch to the keyboard interrupt routine.

At the same time, the keyboard in its own special memory remembers which key was pressed (usually, the keyboard memory can store up to 20 codes of pressed keys if the processor does not have time to respond to the interrupt). After sending the code of the pressed key to the processor, this information disappears from the keyboard memory.

In addition to pressing, the keyboard also notes the release of each key, sending the processor its interrupt signal with the corresponding code.

Characters are entered from the keyboard only at the point on the screen where the cursor is located. The cursor is a rectangle or a line of contrasting color one character long.

Special keyboard keys: Special (service) keys perform the following main functions: (ENTER) - entering commands for execution by the processor; (ESC) - cancellation of any action; (TAB) -moves the cursor to the tab stop; (INS) -switching the mode of inserting a character at the cursor position to the mode of backing up the character at the cursor position;

(DEL) -deleting a character at the cursor position;

(BACKSPACE) -delete the character to the left of the cursor;

(HOME) -moves the cursor to the beginning of the text;

(END) -moves the cursor to the end of the text;

(PGUP) -move the cursor one screen page up through the text;

(PGDN) -move the cursor one screen page down the text;

(ALT) and (CTRL) -when these keys are pressed simultaneously with any other, the action of the latter is changed;

(SHIFT) - keeping this key pressed provides a case change;

(CAPS LOCK) -fixing / unlocking the case of capital letters;

EXTERNAL MEMORY Used for long-term storage of information Solid-state storage media Hard disk drives (HDD, HDD) HARDWARE IMPLEMENTATION Magnetic tape drives - "Streamers" Laser drives (CD, Compact Disk, etc.) Storage medium - recording medium / reading and storing information.

Variant of classification of information carriers used in computer technology Information carriers for computers Magnetic tape carriers Optical disc carriers Magneto-optical flash carriers

The main type of external memory is magnetic memory. Magnetic recording At the end of 1898, the Dane Valdemar Poulsen proposed a device for magnetic recording of sound on steel wire. Thirty years later, German engineer Fritz Pfleumer introduced a tape recorder with a thin steel coating on it. In 1932, the German company AEG demonstrated the first sound recording apparatus, which was named "Magnetophon". Magnetic tape has the main disadvantage - the ability to demagnetize during long-term storage and has an uneven frequency response (different sensitivity to recording at different frequencies). In addition, any magnetic tape has its own noise (physical properties of the magnetic layer and methods for recording and reproducing sound).

The principle of magnetic recording is the effect of an electromagnetic field on the ferromagnetic material of a magnetic tape, carried out during recording, as well as rewriting an analog signal. During recording, the magnetic field changes in accordance with changes in electrical signals. Electrical vibrations from the sound source are fed to the recording head and excite a magnetic field of sound frequency (20 Hz - 20 kHz) in it. Under the influence of this field, the magnetization of individual sections of the magnetic tape occurs, evenly moving along the recording, erasing and playback heads (Fig.).

For recording and playback, as well as the use of various data on computer-readable data carriers, the conversion of an analog (audio and video) signal into digital form is used. This technology is called information digitization. The principle of digitization (coding) of sound consists in converting continuous, different in magnitude, amplitude-frequency audio and video signals into a coded sequence of numbers representing discrete values \u200b\u200bof the amplitudes of this signal taken after a certain period of time. To do this, it is necessary to measure the signal amplitude at certain time intervals and determine the average signal amplitude at each time interval. According to the Chenon (Kotelnikov) theorem, this time interval (frequency) must be at least twice the maximum frequency of the transmitted sound signal (Fig.).

This frequency is called the sampling rate. Sampling is the process of taking samples of a signal that is continuous in time at points equally spaced from each other in time, which make up the sampling interval. The sampling process measures and stores the level of the analog signal. Amplitude Frequency (Hz) Fig. 13. Converting analog signal to digital. The less frequent (less) time intervals, the higher the quality of the encoded signal.

Tape drives Tape media are used for backups to ensure data integrity. A streamer is used as such devices (Fig.), And - as a data carrier, they use magnetic tapes in cassettes and tape cartridges. Typically, tape records are byte byte, with the domain corresponding to a binary one. If the reader does not detect it, then the received value is zero.

The recording system for magnetic disks and floppy disks is somewhat similar to the recording system for records. Unlike the latter, the recording is carried out not in a spiral, but on concentric circles - tracks ("tracks" - traks), located on both sides of the disc and forming, as it were, cylinders. Circles, in turn, are divided into sectors (Fig.). Each sector of a floppy disk, regardless of the size of the track, has the same size, equal to 512 bytes, which is achieved by different recording densities: less on the periphery and more closer to the center of the floppy.

Magneto-optical data carrier external highly reliable devices for transferring and storing information. Magneto-optical disks (MO) appeared in 1988. The MO disk is enclosed in a plastic envelope (cartridge) and is a random access device. It combines magnetic and optical principles of information storage and represents a polycarbonate substrate (layer) with a thickness of 1, 2 mm, on which several thin-film magnetic layers are applied (Fig.). Laser recording with a temperature of about 200 ° C. From to the magnetic layer occurs simultaneously with the change in the magnetic field. Figure: The composition of the MO disk.

Data recording is carried out by a laser in the magnetic layer. Under the influence of temperature at the place of heating in the magnetic layer, the resistance to polarity reversal decreases, and the magnetic field changes the polarity at the heated point to the corresponding binary unit. At the end of heating, the resistance increases, but the set polarity remains. Erasing creates the same polarity in a magnetic field, corresponding to binary zeros. In this case, the laser beam sequentially heats the area to be erased. The reading of the recorded data in the layer is performed by a laser with a lower intensity, which does not lead to heating of the read area. At the same time, unlike CDs, the surface of the disc does not deform.

A compact optical disc (CD) is a specially coated plastic disc that digitally stores recorded information. Due to the change in the speed of its rotation, the track relative to the readout laser beam moves at a constant linear speed. The speed is higher at the center of the disc, and slower at the edge (1, 2–1, 4 m / s). The CD uses a laser with a wavelength of \u003d 0.78 μm. The digital information "burned through" by the laser is stored in the form of "pits" - lines 0.6–0.8 µm wide and 0.9–3.3 µm long. There are three main types of CDs: ● CD-ROMs, on which recording, as a rule, is carried out in the factory by stamping from a matrix; ● CD-R, used for one or more laser recording sessions; ● CD-RWs designed for multiple erasure cycles.

The CD-R (Compact Disk Recordable) has an organic layer of special fusible plastic on top of a reflective layer of gold, silver or aluminum. Because of this, such a disk is sensitive to heat and direct sunlight. In CD-RW, an organic compound is also used as an intermediate layer, but it is capable of transforming from a crystalline (transparent for a laser) state to an amorphous state under strong heating. Mild heating returns it back to its crystalline state. Thus, overwriting is carried out.

DVD In early 1997, a compact disc standard called DVD (Digital Video Disc) emerged, primarily for recording high-quality video programs. Subsequently, the abbreviation DVD received the following meaning - Digital Versatile Disc, as it more fully meets the capabilities of these discs for recording audio, video, text information, PC software, etc. DVD provides a higher image quality than CD. They use a laser with a shorter radiation wavelength \u003d 0.635-0.66 µm. This makes it possible to increase the recording density, i.e., to reduce the geometrical dimensions of the pit to 0.15 µm and the track pitch to 0.74 µm.

The recording density of optical discs is determined by the laser wavelength, that is, the ability to focus on the surface of the disc a beam with a spot, the diameter of which is equal to the wavelength. After DVD, at the end of 2001, Blu-Ray devices appeared, allowing to work in the blue region of the spectrum with a wavelength of 450–400 nm.

To increase the capacity, fluorescent discs are also used - FMD (Fluorescent Multilayer Disk). Their principle of action is to change the physical properties (the appearance of a fluorescent glow) of some chemicals under the influence of a laser beam (Fig.). Here, instead of CD and DVD technologies, which use a reflected signal, under the influence of a laser, light is emitted directly by the information layer. These discs are made of transparent photochrome. Under the influence of laser radiation, a chemical reaction takes place in them, and individual sections of the information layer ("pita") are filled with fluorescent material. This method can be considered a bulk data recording method. To a greater extent, such a recording is possible when using three-dimensional holography, which now makes it possible to place up to 1 TB of data in a crystal the size of a sugar cube.

There are two main types of Flash memory used: NAND and NOR (logical NOR function) and NAND (logical NAND function). The NOR structure consists of parallel information storage unit cells. Such an organization of cells provides random access to data and byte-by-byte writing of information. The structure of NAND is based on the principle of sequential connection of unit cells, forming groups (16 cells in one group), which are combined into pages, and pages into blocks. With this construction of the memory array, access to individual cells is impossible. Programming is carried out simultaneously only within one page, and when erasing, blocks or block groups are accessed.

NOR chips work well together with RAM, therefore they are more often used for BIOS. When dealing with relatively large amounts of data, write / erase processes in NAND memory are significantly faster than in NOR memory. Since the 16 adjacent NAND memory cells are connected in series with no contact gaps, a high density is achieved on the chip, which allows for high capacity at the same technological standards. Since the mid-1990s. NAND chips appeared in the form of solid-state drives (Solid State Disk, SSD). For comparison, the access time for SDRAM is 10–50 μs, for flash memory - 50–100 μs, and for hard drives - 5000 - 10000 μs.

Samsung Solid State Hard Drive. The read speed from such a disk is 57 MB / s, and the write speed to it is 32 MB / s. SSDs consume less than 5% of the power consumption of traditional hard drives, increasing laptop battery life by more than 10%. SSDs provide ultra-high reliability of data storage and have proven themselves in extreme temperatures and humidity. Petersburg firm “Prosto. Soft ”offered the Flash driver. RAID for combining two flash drives into a RAID array.

Flash memory is a portable non-volatile storage device. The following flash memory standards are commonly used: Compact. Flash, Smart. Media, Memory Stick, Floppy Disks, Multi. Media Cards, etc. They can be used instead of floppy disks, laser and magneto-optical compact, small hard drives. Modern removable flash memory devices provide high speed of data exchange (Ultra High Speed) - more than 16, 5 Mbit / s. To connect to the USB port of a computer, special USB Flash Drives are used (Fig.), Which are mobile small-sized data storage devices that do not have moving and rotating mechanical parts.

Holography is a photographic method of recording, reproducing and transforming wave fields. It was first proposed in 1947 by the Hungarian physicist Dennis Gabor. In the 1960s, with the advent of the laser, it became possible to accurately record and reproduce volumetric images in a lithium niobate crystal. Since the 1980s, with the advent of compact discs, holographic storage devices based on laser optics have become one of the external memory technologies. The holographic memory represents the entire volume of the storage medium of the medium, while the data items are accumulated and read in parallel.

Modern holographic storage devices are called HDSS (holographic data storage system). They contain: a laser, a beam splitter for splitting a laser beam, mirrors for directing laser beams, a liquid crystal panel used as a spatial light modulator, lenses for focusing laser beams, a lithium niobate crystal or photopolymer as a memory device, a photodetector for reading information (Fig.) ...

Classification of long-term storage devices

The most common are magnetic disk drives, which are divided into hard disk drives (HDDs) and floppy disk drives (floppy disks), and optical disk drives such as CD-ROMs, CD-Rs, CD-RWs and DVD-ROM.

Detailed characteristics of long-term storage devices

Hard disk drives (HDD)

HDD is the main device for long-term storage of large amounts of data and programs. Other names: hard disk, hard drive, HDD (Hard Disk Drive). Outwardly, the hard drive is a flat, hermetically sealed box, inside which there are several rigid aluminum or glass round plates on a common axis. The surface of any of the disks is covered with a thin ferromagnetic layer (a substance that reacts to an external magnetic field), which actually stores the recorded data. In this case, the recording is carried out on both surfaces of each plate (except for the extreme ones) using a block of special magnetic heads. Each head is located above the working surface of the disk at a distance of 0.5-0.13 microns. The disk stack rotates continuously and at high frequency (4500-10000 rpm), therefore, mechanical contact between heads and disks is unacceptable.

There are a huge number of different models of hard drives from many companies such as Seagate, Maxtor, Quantum, etc. To ensure the compatibility of hard drives, standards have been developed for their characteristics, which determine the nomenclature of connecting conductors, their placement in adapter connectors, and electrical parameters of signals. Common are the IDE (Integrated Drive Electronics) or ATA interface standards and the more productive EIDE (Enhanced IDE) and SCSI (Small Computer System Interface). The characteristics of the interfaces through which the hard drives are connected to the motherboard largely determine the performance of modern hard drives.

Other parameters that affect HDD performance include the following:

• § disk speed - nowadays EIDE drives are produced with a speed of 4500-7200 rpm, and SCSI drives - 7500-10000 rpm;
• § cache memory capacity - a cache buffer is installed in all modern disk drives, which accelerates data exchange; the larger its capacity, the higher the likelihood that the cache will contain the necessary information that does not need to be read from the disk (this process is thousands of times slower); the capacity of the cache buffer in different devices can vary from 64 KB to 2 MB;
• § Average access time - the time (in milliseconds) during which the head block moves from one cylinder to another. Depends on actuator design and is approximately 10-13 milliseconds;
• § delay time is the time from the moment the head unit is positioned to the desired cylinder to the positioning of a specific head to a specific sector, in other words, it is the search time for the desired sector;
• § exchange rate - determines the amount of data that can be transferred from the drive to the microprocessor and in the opposite direction within certain periods of time; the maximum value of this parameter is equal to the bandwidth of the disk interface and depends on which mode is used: PIO or DMA; in PIO mode, data exchange between the disk and the controller takes place with the direct participation of the central processor, the higher the PIO mode number, the higher the exchange rate; operation in DMA (Direct Memory Access) mode allows data to be transferred directly to RAM without the participation of a processor; The data transfer rate in modern hard drives ranges from 30-60 MB / s.
• Floppy disk drives (floppy disk drives)

The floppy disk drive or disk drive is built into the system unit. Flexible media for floppy disk drives are produced in the form of floppy disks (another name for floppy disk). Actually, the carrier is a flat disc with a special, rather dense film covered with a ferromagnetic layer and placed in a protective envelope with a movable latch in the upper part. Floppy disks are mainly used to quickly transfer small amounts of information from one computer to another. The data recorded on the floppy disk can be protected from erasure or overwriting. To do this, move the small safety latch at the bottom of the floppy disk so that an open window is formed. To enable recording, this latch should be moved back and the window closed.

The main parameters of a floppy disk are technological size (in inches), recording density and total capacity. There are 3.5-inch floppy disks and 5.25-inch floppy disks (no longer used) by size. The recording density can be simple SD (Single Density), double DD (Double Density) and high HD (High Density). The standard capacity of a 3.5-inch floppy disk is 1.44 MB, and 720 KB floppy disks can be used. The current standard is 3.5-inch HD high-density floppy disks with a capacity of 1.44 MB.

CD-ROM drive

Since 1995, a CD-ROM drive has been included in the basic configuration of a personal computer instead of 5.25-inch drives. The abbreviation CD-ROM (Compact Disk Read Only Memory) translates as read-only storage device based on compact discs. The principle of operation of this device is to read digital data using a laser beam that is reflected from the surface of the disc. An ordinary CD is used as a storage medium. Digital recording on a CD is different from recording on a magnetic disc in high density, so a standard CD has a capacity of about 650-700 MB. Such large volumes are typical for multimedia information (graphics, music, video), so CD-ROM drives are classified as multimedia hardware. In addition to multimedia publications (e-books, encyclopedias, music albums, videos, computer games), a variety of system and application software of large volumes (operating systems, office suites, programming systems, etc.) is distributed on CDs.

Compact discs are made of transparent plastic with a diameter of 120 mm and a thickness of 1.2 mm. A layer of aluminum or gold is sprayed onto the plastic surface. In conditions of mass production, information is recorded on a disc by extrusion on the surface of the track, in the form of a series of recesses. This approach provides a binary record of information. Deepening (pit), surface (land). Logical zero can be represented by either a pet or a land. The logical unit is encoded by the transition between the pet and the land. From the center to the edge of the CD, there is a single track in the form of a spiral 4 microns wide with a pitch of 1.4 microns. The disc surface is divided into three areas. Lead-In is located in the center of the disc and is read first. It contains the contents of the disk, the table of addresses of all records, the disk label and other service information. The middle area contains basic information and takes up most of the disk. Lead-Out contains the disc end mark.

For stamping, there is a special prototype matrix (master disc) of the future disc, which squeezes the tracks onto the surface. After stamping, a protective film made of transparent varnish is applied to the surface of the disc.

Main features of CD-ROM:

• § data transfer rate - measured in multiples of the speed of an audio CD player (150 Kbytes / sec) and characterizes the maximum speed at which the drive transfers data to the computer's RAM, for example, 2-speed CD-ROM (2x CD-ROM) will be read data at a speed of 300 KB / sec., 50-speed (50x) - 7500 KB / sec;
• § access time - the time required to search for information on the disk, measured in milliseconds.

The main disadvantage of standard CD-ROMs is the inability to write data, but there are CD-R write-once and CD-RW re-write devices.

CD-R drive (CD-RECORDABLE)

Externally similar to CD-ROM drives and compatible with them in disk sizes and recording formats. Allows one-time write and unlimited reads. Data recording is carried out using special software. The write speed of modern CD-R drives is 4x-8x.

CD-RW drive (CD-REWRITABLE)

They are used for reusable data recording, and you can either simply add new information to the free space, or completely overwrite the disk with new information (the previous data is destroyed). As with CD-R drives, to write data, you need to install special programs in the system, and the recording format is compatible with a regular CD-ROM. The write speed of modern CD-RW drives is 2x-4x.

DVD drive (DIGITAL VIDEO DISK)

Digital video reader. Externally, a DVD is similar to a regular CD-ROM (diameter - 120 mm, thickness 1.2 mm), but differs from it in that up to 4.7 GB can be recorded on one side of a DVD, and up to 9.4 GB. In the case of using a two-layer recording scheme, one side can already accommodate up to 8.5 GB of information, respectively, on both sides - about 17 GB. DVDs are rewritable.

DVD Perspectives

The presence of different standards and specifications does not mean that DVD technology stands still. The efforts of various companies today are aimed at introducing the "blue laser" technology - with a shorter wavelength. This will increase the recording density on discs with the ensuing improvement in other characteristics.

Calimetrics Inc has introduced ML (multilevel) technology that triples the capacity of a standard DVD / CD. At the same time, there is no need to make any modifications in the mechanism and optics of the existing drives. To implement a new technology, it is enough to use a chipset developed by this company. The essence of the technology lies in the ability to use the depth of pits (up to 8 levels) as an information characteristic when working with disks. Note that a similar technology, but for CDs, is being developed by TDK in cooperation with other companies.

• Read-only DVD formats
• DVD-ROM (Digital Versatile Disc Read Only Memory)

DVD-ROM discs are intended for computer use. The information is written to the disk only once - during its production.

The progress of DVD devices follows the path traveled by CD in many ways, and is mainly aimed at improving speed characteristics and introducing a recording function. First generation DVD-ROM drives used CLV mode and read from disc at 1.38 MB / s (traditional DVD notation is 1x). Second-generation devices could read DVDs at twice the speed - 2x (2.8 MB / s). Modern DVD-ROM devices - third generation devices - use the rotation control (CAV) mode with a maximum read speed of 4x-6x (5.5 - 8.3 Mb / s) or more. Modern DVD-ROM drives (floppy drives) support reading almost all formats, including CDs.

The DVD-Video format is for video storage and playback. Like DVD-ROM, this specification defines the read-only capability - playback of recordings using video players (video encoders). The specification is based on the DVD-ROM format, but provides a special way to arrange data to prevent bitwise copying of discs. The encoded video materials are placed on the disc during its production. DVD-video playback is possible only on consumer video players (video encoders) or on DVD drives connected to a computer. When using computer equipment, decoding of information is carried out either by hardware or by software. The modern specification provides high-quality video recording to disk (up to 2 hours in MPEG-2 compression format). And also multichannel soundtrack in 8 languages, choice of screen format, captions in 32 languages, interactive control through the on-screen menu, up to 9 angular viewing directions, protection against illegal copying, differentiation of viewing video products by region, control of children's access to video materials.

A new generation of music format after CD. The format specification defines high-quality multichannel sound, support for a wide range of sound quality (quantization of 16, 20, 24 bits at a frequency of 44.1 to 192 kHz), DVD playback by CD players, support for additional information (including video, text, menus, screensavers, convenient navigation system), communication with websites providing information support, expansion of opportunities with the advent of new technologies.

There are two versions of the DVD-Audio format, simply DVD-Audio for audio content only and DVD-AudioV for audio with additional information.

Special measures have been developed to protect disks from pirated copying.

• Reusable DVD formats
• W Multiple recording

All known specifications of rewritable DVD discs use rewritable technology based on the physical principle of phase change (crystalline / amorphous) of the information layer under the influence of a laser with a wavelength of 650 (635) nm (phase-change recording). Information reading is carried out by determining the optical characteristics of the information layer in its various phase states when reflecting laser beams (the same as when recording).

W DVD-RAM (Digital Versatile Disc Random Access Memory)

Rewritable format developed by Panasonic, Hitachi, Toshiba.

The format was approved by the DVD Forum in July 1997. Hardware and discs of this format were tested for 3 months in more than 20 computer manufacturing companies around the world. Over 160 forum members voted in favor of the specification. It is the most widely used DVD format in the computer industry today.

DVD-RAM drives read DVD-ROM discs. In turn, DVD-RAM discs can only be read by so-called third generation DVD-ROM drives manufactured since mid-1999.

The first generation of DVD-RAM discs contained 2.6 GB per side. Modern - second - generation drives carry 4.7 GB on the side or 9.4 GB for double-sided modification.

There are two types of single-sided DVD-RAM discs available - in cartridge and without cartridge. Discs in a cartridge are mainly intended for consumer video equipment, where it is necessary to exclude the influence of external factors during intensive manual use. Cartridges, in turn, can be of two types - openable and solid.

The most important advantages of DVD-RAM discs are the ability to rewrite up to 100,000 times and the presence of a recording error correction mechanism.

The largest number of rewrite cycles of any DVD, an error correction mechanism and random access to the disc, both for writing and for reading, predetermined the maximum efficiency of this format in secondary storage devices. The vast majority of mass storage devices - robotic DVD libraries - use this technology.

DVD-RAM discs can be used for recording and streaming video on equipment that supports the DVD-VR specification (see below).

DVD + RW (Digital Versatile Disc ReWritable)

The DVD + RW format is promoted only by its developers - Hewlett-Packard, Mitsubishi Chemical, Philips, Ricoh, Sony and Yamaha (not supported by the DVD forum).

DVD + RW discs can record both streaming video or sound and computer data. DVD + RW discs can be rewritten about 1000 times.

On the basis of DVD + RW, a streaming video recording format has been created - DVD + RW Video Format. Devices and discs operating in this format are positioned on the market as fully compatible with equipment operating in DVD-Video formats. This means that DVD + RW discs containing video content can be played on previous consumer DVD equipment.

Philips announced the launch of its DVD video recorder in September 2001. DVD + RW discs recorded on this device are also readable by regular DVD-Video players. This solution was proposed as a response to the DVD-Forum's adopted DVD-VR specification (see below).

DVD-RW (Digital Versatile Disc ReRecordable)

There are other names for this format: DVD-R / W and less often DVD-ER.

DVD-RW is a rewritable format developed by Pioneer. DVD-RW discs contain 4.7 GB per side, are available in single-sided and double-sided versions and can be used to store video, audio and other data.

DVD-RW discs can be rewritten up to 1000 times. Unlike DVD + RW and DVD-RAM, DVD-RW discs can be read on first generation DVD-ROM drives.

TDK claims that its DVD-RW discs have a lifespan of approximately 100 years.

• DVD Recordable Formats
• W DVD-R (Digital Versatile Disc Recordable)

DVD-R is a write-once format developed by Pioneer. Devices based on this format were the first to record on DVDs. The recording technology is similar to that used in CD-R and is based on an irreversible change under the influence of a laser in the spectral characteristics of the information layer covered with a special organic compound.

DVD-R discs can contain both computer data, multimedia programs, and video / audio information. Depending on the type of information recorded, discs can be read on other types of devices compatible with the recorded format, including DVD-Video video players and most DVD-ROM drives. Single-sided DVD-R discs can hold 4.7 or 3.95 GB per side. Double-sided discs are available only with a total capacity of 9.4 GB (4.7 GB per side). The format does not currently support dual layer recording technology.

DVD-R discs are estimated to last over 100 years. To prevent illegal copying, two specifications have been developed: DVD-R (A) and DVD-R (G). These two versions of the same specification use different laser wavelengths when recording information. Thus, discs can only be recorded on equipment that meets their specifications. Disc playback can be performed equally well on any equipment that supports the DVD-R format.

DVD-R (A) (DVD-R for Authoring) is used in professional applications. In particular, the support of a special format (Cutting Master Format) allows using these disks for recording the original replica of information (pre-mastering) instead of the usual use of DLT tapes for these purposes.

DVD-R (G) (DVD-R for General) is intended for wider applications. Discs of this format are protected from the possibility of bitwise copying of information on them from other disks. The format is supported by mass storage devices (such as robotic DVD libraries offered by Pioneer itself).

The DVD-VR specification is based on DVD-RAM and is supported by the DVD Forum. The DVD-VR format can record up to 2 hours of high quality MPEG-2 video in real time onto a 4.7GB single-sided DVD-RAM disc, and offers features such as editing video already recorded, recording various types of still images. Electronics based on this format are produced, for example, by Panasonic, Toshiba, Samsung, Hitachi.

And information. Of course, you want to keep things like wedding photos or videos for a long memory. However, how do you do this?

Concept

Informatics defines that all possible storage devices and media that can only be imagined serve for long-term storage of information. As you can imagine, there are different ways to ensure the safety and security of your data. Let's define what forms of information storage exist.

• Graphic / pictorial. The most ancient method, adapted for It appeared in prehistoric times in the form of rock paintings, passed the stage of painting and turned into the art of photography. In addition, information is graphically presented in the form of drawings and diagrams.
• Text. The most common way of storing data today. A variety of books and records, libraries. If we talk about reliability, then this storage method is not only not protected from theft, but also short-lived. Best of all, cookbooks, which are originally printed on materials adapted to a hostile environment, will survive.
• The next step after the invention of writing is mathematics , the numerical form of information storage. A rather highly specialized area, it is used to determine the quantitative characteristics of an object in the surrounding space.
• Sound recording... The ability to store sounds did not appear until 1877 with the invention of sound recording devices.
• Video information... The next step in storing graphic information that appeared with the creation of cinematography.

Information processes

Information processes mean searching, storing, transferring, using, and the main and paramount concern is the preservation of data. What difference does it make if we can receive or transmit information if we cannot save it?

The main one is the process of storing information. It is a way of transmitting data in space and time. For long-term storage of information is a device or device, depending on the type of stored data. Information systems are used to ensure the orderliness of this process. Any such system is equipped with procedures for searching, placing and input / output data. The main distinguishing feature of the information system is the presence of all these key procedures. For example, let's compare two libraries. A private library in your home in a closet is not an information system, since only you are guided by it. On the other hand, a public city library, in which everything is organized in a file cabinet and there are standardized procedures for issuing and receiving books, is undoubtedly a system.

Computer age

With the development of not even a computer, but the Internet, information systems are being modernized. The storage process is simplified by the ability to digitize it. And despite the beliefs of some people that e-books or pictures do not carry souls, this method of storing data serves for long-term storage of information much more efficiently than others, and it includes all possible information, if only you can translate it into digital view.

Modernity

A personal computer and its external devices are used for long-term storage of information. They are classified into several types depending on the recording method.

• optical discs;
• hard drives;
• flash memory.

They have a very different volume and are best suited for transferring and storing information. Hard drives are designed to store large amounts of data, but their reliability leaves much to be desired. And, of course, flash drives. They are the middle link between hard and optical disks, provide storage of information in sufficient volumes and for a sufficiently long period, just do not wet them. In any case, the storage method is up to you.