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System peripherals. Periphery equipment. Transmission of sound and graphic information

Hi all. In today's episode I will continue the topic of computer design and talk about it peripherals. This is the second part of a large article; in the last publication we examined the first part of the computer device - the system unit.

If you haven’t read the first part of the article, then I recommend that you definitely get acquainted with it, in it I talk about the structure of a computer, namely.

Computer peripherals

Well, now it’s time to talk about peripheral devices, let’s look at the most basic ones.

Mouse

The mouse is needed to move the cursor to the required space on the desktop. There are three types of mice: mechanical, with a ball inside; optical and laser.

I remember once using a mechanical mouse before. It was necessary to move the mouse with force across the mat to move the mouse cursor to the desired place on the desktop. There are regular cheap mice and special fancy gaming mice. I have a large rug and a gaming laser mouse at home, which at that time cost about $50.

Keyboard

The keyboard will play an auxiliary role in controlling our computer.

With it you can type text, chat with friends, play different games and much more. My keyboard played an important role in writing this article.

Monitor

Probably nowhere without a monitor. If it weren’t for him, there probably wouldn’t have been a computer either :). The display is needed to display information on the screen, which in turn passes through the video card. Monitors are divided into three groups: cathode ray tube (CRT), liquid crystal display (LCD) and plasma. The latter are most often used to make new televisions.

The average monitor has a diagonal of 15 inches and ends at 32 inches. If there are more inches, then it is already considered a TV.

Most PC users now have LCD monitor s, but there are also CRTs. I use a regular LCD monitor with a diagonal of 19 inches, which is about 48 centimeters, almost half a meter, which suits me quite well.

Speakers and headphones

Headphones and sound speakers necessary to output sound from the computer to our ears. Every computer and laptop has a sound card. Mostly they are built into the motherboard.

If you have good speakers If you have audio files in high quality and you want to listen to them with pleasure, you can buy a separate sound card. Decent audio speakers cost about $100, of course there are cheaper ones, but why buy a cheap one if a similar one is already built into the motherboard.

There are times when the internal sound card is broken. You can, of course, try to resolder the connector or sound chip, but not everyone understands this. Therefore, to solve this problem, you can completely replace the motherboard or purchase an inexpensive external sound card.

It is advisable to use speakers made of wood, they have quite good sound transmission capacity, but plastic ones are also not bad. The more watts your speakers can pump out, the clearer and louder the sound will be.

Modem

Modem is network device, which was invented to use it to access the Internet and communicate with other users.

Dial Up modems

There used to be simple slow 56k modems. The number 56 means the data transfer rate is 56 kbit/sec. I remember a couple of years ago I worked in a company where we used just such modems.

For those who don't know, I'll post it soundtrack Modem dial-up noise when it goes online. And those who remember these times, just listen. When I heard him, for some reason a smile appeared on my face.

Dial-Up Modem-Connekt

In some remote populated areas and villages still use such dial-up modems.

ADSL modems

On this moment Probably in all major cities they use high-speed Internet, using ADSL modems, dedicated VPN channels, wireless Wi-Fi and others.

Webcam

A webcam is needed to transmit pictures, video images, and sometimes sound if there is a built-in microphone. Using a webcam, you can talk to a person both in the next room and in another country, using the Internet and third-party programs.

Microphone

A microphone is needed to record or transmit your voice. Most webcams and headphones with a microphone have it.

USB drives

USB drives include small devices that store information on flash drives and hard drives. This device is universal; it can probably be connected to any computer via a USB port.

The volumes of flash drives are different, starting from 128 Megabytes and ending with 1 Terabyte. USB hard drives have larger storage capacities, of course.

Printer

A printer is needed to print any information, documents, photographs, and so on.

They are matrix, inkjet and laser. I recently learned that printers have appeared that use wax tubes instead of cartridges and toner.

Scanner

A scanner was invented to scan (read) information from printed and other media, then enter it into a computer.

If you frequently scan documents, then this tool is a must-have.

UPS or oops

Sources uninterruptible power supply or rectifiers alternating current are needed so that if a voltage drop occurs, they level out such surges.

Also, if your lights suddenly turn off, your computer will be able to work within 5 - 10 minutes.

Joysticks and game controllers

Using joysticks and game controllers, you can comfortably play various computer games. Children and teenagers really like them.

That's basically all the main ones peripherals, there are, of course, others, but they are less used than those listed above.

Conclusion

Today we talked in detail about the structure of the computer and its peripheral components which include: mouse, keyboard, monitor, speakers and headphones, modem, webcam, microphone, USB drives, printer, scanner, UPS, joysticks and game controllers.

Peripherals computer | website

Perhaps you have or have questions related to the design of your computer and its peripheral devices. You can ask them below in the comments to this article, and also use the form with me.

Thank you for reading me on

The main purpose of the PU is to ensure that programs and data are supplied to the PC from the environment for processing, as well as the output of the results of the PC in a form suitable for human perception or for transfer to another computer, or in another necessary form. Peripheral devices can be divided into several groups according to their functionality:

    I/O devices – designed to input information into a PC, output it in the format required by the operator, or exchange information with other PCs. This type of control unit includes external drives (tape, magneto-optical) and modems.

    Output devices – designed to display information in the format required by the operator. This type of peripheral devices includes: printer, monitor (display), audio system.

    Input Devices – Input devices are devices through which information can be entered into a computer. Their main purpose is to implement an impact on the machine. This type of peripheral devices includes: keyboard (included in the basic PC configuration), scanner, graphics tablet, etc.

    Additional control units - such as a mouse manipulator, which only provides convenient control graphical interface PC operating systems and does not have distinct functions for input or output of information; WEB-cameras that facilitate the transmission of video and audio information on the Internet, or between other PCs.

Chapter 2. Peripheral input devices

2.1 External drives

Tape (magnetic) drives – streamers. Thanks to the fairly large volume and quite high reliability most often used within devices Reserve copy data in enterprises and large companies(store backup copies of databases and other important information). It's not just saved to a tape drive backup copy data, but also creates an image of the data storage. This allows the user to restore a specific state or use this image as a reference data bank, for example when data has been changed. The principle of recording on magnetic media is based on changes in magnetization individual areas magnetic layer of the carrier. Recording is carried out using a magnetic head, which creates a magnetic field. When reading information, magnetized areas create weak currents in the magnetic head, which turn into binary code, corresponding to what was recorded.

Magneto-optical drives – CD-ROM, CD-R, CD-RW, DVD-R, DVD-RW drives. They can also be used as backup devices, but, unlike streamers, they have a much smaller data capacity (CD-R, CD-RW up to 700 MB of data, DVD-R, DVD-RW up to 4.7 GB of data). Information on magneto-optical CD-R drives is represented by alternating depressions and peaks. This relief is created mechanically during production. Information is applied along thin tracks. Reading occurs by scanning the tracks with a laser beam, which is reflected differently from the depressions and peaks. On disks that allow multiple rewrites, the magneto-optical principle is used, which is based on a physical property: the reflection coefficient of a laser beam from differently magnetized areas of a disk with a specially applied magnetic coating is different.

2.2 Flash cards

As soon as computers learned to process data arrays, the problem arose of where and how to store and transfer this data. There were many solutions - from paper punched cards to magnetic tapes and disks. Each of the technologies had many advantages and, as usual, even more disadvantages. We are all prone to laziness, looking for the most pleasant and comfortable conditions, and are not ready to make sacrifices if fashion does not require it. And therefore, as soon as the personal computer lost its status as a prestigious and expensive toy, users, in an increasingly demanding manner, began to hint to manufacturers about the inconvenience of handling them. Today the subject of our conversation is removable memory. Users have several modest requirements for this type of memory:

    Energy independence – i.e. do not need batteries, the unexpected discharge of which will lead to loss of information.

    Reliability - do not lose data under the influence of a thunderstorm, fall or fall into a puddle.

    Compact - so as not to think about whether it’s worth carrying all this with you.

    Durable - so as not to run to the store every month for a new one, because the old one has served its time.

    Universal – compatible with many devices that may require data.

2.3 Modems

Currently, there are two types of modems: analog and digital (xDSL technology).

Analogue modems are more popular because of their low cost and are used mainly for accessing the Internet, and only sometimes (due to the low (up to 56 Kbps) data transfer speed) for communication with other PCs. Digital modems are quite expensive and are used for high speed connections With Internet, or for organization local network over long distances (xDSL modems allow you to transmit and receive information at speeds of up to 5 Mbit/s at a distance of 5-7 km).

Modems have several types of connections to a PC: COM, USB or (for digital modems) via a network card. A modem connected via a COM port requires additional source(supply) power supply, and when connected via a USB port, the need for a power supply is eliminated. xDSL modems also require an additional power source.

Chapter 3. Peripheral information output devices.

Peripheral output devices are designed to display information in the format required by the operator. Among them there are mandatory (included in the basic PC configuration) and optional devices.

3.1 Monitors

The monitor is necessary device information output. A monitor (or display) allows you to display alphanumeric or graphic information on the screen in a form that is easy for the user to read and control. In accordance with this, there are two operating modes: text and graphic. IN text mode the screen is presented in rows and columns. IN graphic format The screen parameters are set by the number of dots horizontally and the number of dot lines vertically. Number of horizontal and vertical lines screen resolution is called resolution. The higher it is, the more information can be displayed on a unit of screen area.

    Digital monitors. The simplest - a monochrome monitor allows you to display only black and white image. Digital RGB monitors (Red-Green-Blue) support both monochrome and color modes (with 16 shades of color).

    Analog monitors. Analog signal transmission occurs in the form of different voltage levels. This allows you to create a palette with shades of varying degrees of depth.

    Multi-frequency monitors. The video card generates synchronization signals that relate to the horizontal line frequency and vertical frame repetition rate. The monitor must recognize these values ​​and switch to the appropriate mode.

CRT monitor According to the possibility of customization, we can distinguish: single-frequency monitors, which perceive signals of only one fixed frequency; multi-frequency, which perceive several fixed frequencies; multi-frequency, tuning to arbitrary frequencies of synchronous signals in a certain range.

    Liquid crystal displays (LCD). Their appearance is associated with the struggle to reduce the size and weight of portable computers.

The main disadvantage is the impossibility quick change pictures or rapid movement of the mouse cursor, etc. Such screens need additional lighting or in external lighting. The advantages of these screens are a significant reduction in the range of harmful effects.

    Gas plasma monitors. They do not have the limitations of LCD screens. Their disadvantage is their high energy consumption.

It is especially necessary to highlight the group of touch screens, since they allow not only to display data on the screen, but also to enter it, that is, they fall into the class of input/output devices. This one is relatively new technology has not yet received widespread use. Such screens provide the easiest and shortest way to communicate with a computer: you just need to point to what interests you. The input device is completely integrated into the monitor. Used in information and reference systems.

3.2 Printers

A printer is a widespread device for outputting information onto paper; its name is derived from the English verb to print - to print. The printer is not included in the basic PC configuration. There are different types of printers:

    A typical printer operates similarly to an electric typewriter. Advantages: clear image of characters, ability to change fonts when replacing a standard disk. Disadvantages: printing noise, low speed printing (30-40 characters/sec.), printing of graphic images is impossible.

    Matrix (needle) printers are the cheapest devices that provide satisfactory print quality for a wide range of people. routine operations(mainly for preparing text documents). They are used in savings banks, in industrial environments where roll printing, printing on books and thick cards and other media made of thick material is necessary. Advantages: acceptable print quality, provided there is a good ink ribbon, and the ability to print as a carbon copy. Disadvantages: rather low printing speed, especially graphic images, significant noise level. Among the motherboard printers, there are also quite fast devices (the so-called Shuttle printers).

    Inkjet printers provide higher quality printing. They are especially useful for displaying color graphics. Using ink of different colors produces a relatively inexpensive image acceptable quality. The color model is called CMYB (Cyan-Magenta-Yellow-Black) after the names of the primary colors that form the palette.

Inkjet printers are much less noisy. Print speed depends on quality. They are quite effective when creating advertising brochures, calendars, and greeting cards. This type of printer occupies an intermediate position between dot matrix and laser printers.

    Laser printers have even higher print quality, close to photographic. They are much more expensive, but the printing speed is 4-5 times higher than that of dot matrix and inkjet printers. The disadvantage of laser printers is that they have rather strict requirements for the quality of the paper - it must be thick enough and should not be loose, printing on plastic-coated paper, etc. is unacceptable.

Laser printers are especially effective in producing original layouts of books and brochures, business letters and materials requiring high quality. They allow you to high speed print graphics, drawings.

    LED printers are an alternative to laser ones. The developer is OKI.

Thermal printers. Used to obtain photographic quality color images. They require special paper. These printers are suitable for business graphics. Printer based on Micro Dry technology. These printers produce full photo-natural colors and have the highest resolution. This is a new competitive direction. Much cheaper than laser and inkjet printers. Developed by Citizen. Prints on any paper and cardboard. The printer operates at low noise levels.

3.3 Plotters (graph plotters).

This device is only used in certain areas: drawings, diagrams, graphs, diagrams, etc. Plotters are widely used in conjunction with programs of automatic design systems, where design or technological documentation becomes part of the results of the program. Plotters are also indispensable when developing architectural projects. The plotter's drawing field corresponds to A0-A4 formats, although there are devices that work with a roll that do not limit the length of the output drawing (it can be several meters long). That is, there are flatbed and drum plotters.

    Flatbed plotters, mainly for A2-A3 formats, fix the sheet and draw a drawing using a writing unit that moves in two coordinates. They provide higher accuracy of printing of drawings and graphs compared to drum printing.

    The roll (drum) plotter remains in fact the only developing type of plotter with a roller sheet feed and a writing unit moving along one coordinate (the paper moves along another coordinate).

Distributed cutting plotters to print the drawing on film, instead of a writing unit, they have a cutter. Plotters usually communicate with a computer via a serial (COM), parallel (LPT) or SCSI interface. Some plotter models are equipped with a built-in buffer (1 MB or more).

3.4 Projection technology

Multimedia projector allows you to play on big screen information received from a wide variety of signal sources: computer, VCR, video camera, photo camera, DVD player, game console. The image in a multimedia projector is formed in several main ways: using liquid crystal panels (LCD technology) and using DMD micromirror chips (DLP technology). In LCD projectors, the light from the lamp passes through a liquid crystal panel, on which a picture is created, like a regular film, but using a digital electronic circuit. Light passes through the panel and lens, and as a result, an image magnified many times is projected onto the screen. In DLP projectors, the light from the lamp is reflected from many electronically controlled micromirrors and also hits the screen through the lens.

3.5 Audio system

Personal computers use a wide variety of sound signal generation schemes, from simple to complex. It seems that the problem with sound for personal computers has been finally solved. It's rare to see motherboards not equipped with an audio controller. However, even if we consider the issue with audio cards closed, the topic of speaker systems remains a burning issue. This question remains pressing, because many users do not limit themselves to watching videos and playing games with surround sound. True audiophiles prefer high-quality stereo sound with surround sound and deep bass, not to mention enthusiasts who create music using their personal computers. For them it is generally a mandatory element home studio is high-quality stereo acoustics, even if the rest of the role is assigned to a computer with a sound card. These days there are a lot of speaker systems on the market that consist of two active speakers and are made using a 2.1 system. Similar systems They are popularly called “tweeters” because they are not able to provide high quality sound even at low volume levels. More recently, the ideal in the world of computer (and not only) speaker systems was a 5.1 system (five satellites and one subwoofer), but in Lately Acoustic manufacturers are expanding the capabilities of their systems, which led first to the emergence of the 6.1 system, and later 8.1

Chapter 4. Peripheral input devices.

Input devices are those devices through which information can be entered into a computer. Their main purpose is to implement an impact on the PC.

4.1 Keyboard

The main input device for most computer systems is the keyboard. Until recently it was used standard keyboard, 101/102 keys (the first keyboard model contained only 83 keys), but with the development of personal computers, manufacturers tried to develop the main information input device. This led to the creation of multimedia keyboards, with much big amount buttons, which are becoming more and more popular these days.

TO additional keys include groups of control keys multimedia applications(for example, calling and controlling video viewing programs), system volume control keys, a group of keys for quick call office applications(Word, Excel), calculator, Internet Explorer etc. Keyboards differ in two ways: connection method and design. The keyboard can be connected to the computer via the PS/2 port, USB and via the IR (infrared) port for wireless models. IN the latter method connection, the keyboard requires an additional power source, such as a battery.

4.2 Scanner

For direct reading graphic information optical scanners are used from paper or other media to a PC. The scanned image is read and converted into digital form by elements of a special device: CCD chips. There are many types and models of scanners. Which one to choose depends on the tasks for which the scanner is intended. The most simple scanners recognize only two colors: black and white. These scanners are used to read bar codes.

    Hand-held scanners are the simplest and cheapest. The main disadvantage is that the person himself moves the scanner around the object, and the quality of the resulting image depends on the skill and steadiness of the hand. Another important drawback is the small scanning bandwidth (up to 10 cm), which makes reading wide originals difficult.

    Drum scanners are used in professional printing activities. The principle is that the original on the drum is illuminated by a light source, and photosensors convert the reflected radiation into a digital value.

    Sheet scanners. Their main difference from the previous two is that during scanning, a ruler with CCD elements is fixedly fixed, and the sheet with the scanned image moves relative to it using special rollers.

    Flatbed scanners. This is the most common type for professional work today. The object to be scanned is placed on a glass sheet, the image is read line by line at a uniform speed by a reading head with CCD sensors located at the bottom. Flatbed scanner can be equipped with a special slide attachment device for scanning transparencies and negatives. Slide scanners were previously used to scan slides and microimages.

    Projection scanners. A relatively new direction. A color projection scanner is a powerful multifunctional tool for inputting any color images, including three-dimensional ones, into a computer. It can easily replace a camera.

Nowadays, scanners have another application - reading handwritten texts, which are then converted into ASC codes II and can be further processed by text editors.

The interface may be different:

    Own interface - the scanner comes with its own unique card and works only with it. This card may not work in your personal computer or may fail.

    SCSI – if you use the scanner not with the card supplied, then easy compatibility is not always achieved.

    LPT (and its variants, with support or requirement for EPP, ECP or Bi-Directional) - the scanner may need to support one of the high-speed protocols by the port. While EPP is usually always available, the 8-bit Bi-Directional option required for Epson scanners is not implemented everywhere.

    USB is the most common connection option today. It’s easy to connect and, if you have all the drivers and programs, it always works.

4.3 Graphics tablet

Desktop computers for engineering and design work have been equipped with graphics tablets for more than ten years. This device greatly simplifies the entry of drawings, diagrams and drawings into a PC. At first, tablets were expensive devices and therefore were designed for purely professional use. But cheap home models have been produced for about five years now. Even despite good hand-drawing skills, you are unlikely to be able to draw anything useful in a graphics editor by moving your mouse. The pen and tablet are a game-changer. If we add to this the emergence of new opportunities for graphic editors. It's about about sensitivity to pressure. Depending on the force with which you draw the line, its thickness and transparency change in the program window. The transparent film covering the tablet allows you to trace the originals - i.e. You can put a picture under it and, tracing its lines with the tip of the pen, repeat the drawing in the editor window.

Chapter 5. Additional peripheral devices.

5.1 Manipulators

A mouse is one of the pointing input devices that provides a user interface with a computer. There are two types of mice: ball mice and optical mice.

    Used in ball pointers mechanical method transmitting the direction of movement (the ball located at the bottom of the manipulator, when moving, rotates two rollers located inside).

    Optical mice use an LED instead of a ball.

The mouse has several connection types: COM, PS/2, USB, IR (infrared port). “Mice” with a connection type using a COM port are one of the first manipulators. Basically they were equipped with two buttons. It stayed on the market for quite a long time. PS/

A peripheral device is computer hardware that is structurally separate from the PC itself, but at the same time functions under its control. Such devices are intended to expand functionality personal computer: organizing input/output, printing typed texts and images, exchanging data with other personal computers, to control a variety of external devices, including household appliances.


This peripheral device is designed for printing various text and graphic information: photographs, drawings, typed texts, graphs, drawings, etc.

Whenever possible, colors are divided into:

  1. Colored with the ability to print not only color pictures, but also full-fledged photographs (photo printers);
  2. Black and white, which print simple text and graphics in shades of gray, but without the ability to output color.

Structurally, existing printing devices can be divided into:

  • Matrix, where the print head contains “needles” that hit the paper through the ink ribbon and form characters and images. The resolution of such printers can reach 300 dots per inch (dpi), and the number of needles in the head is 9 and 24 pieces. Flaw– low printing speed and increased noise, but at the same time, such devices have the lowest cost per print and the ability to print using a carbon copy;
  • Jet, the very name of which speaks for itself - printing is carried out by a controlled stream of ink using nozzles in the print head. Inkjet printers are available in both black and white and color, and color inkjet printers are excellent for printing photographs due to their high resolution (600-900 dpi) and excellent characteristics color rendition. Printing speed reaches 10-20 pages per minute.
    The main disadvantage such devices is the fact that if the printer is not used for a long time, the print head quickly becomes unusable (the nozzles become clogged), and the cost of replacing it is comparable to the cost of the printer;
  • Laser where the formation of an image on paper occurs using xerography. The image is transferred to paper using a laser beam and a special powder, which is poured into a special cartridge. Laser printers are characterized by high resolution (up to 1200 dpi for black and white and up to 2400 for color), high speed printing (up to 60 pages per minute), fairly low cost per print, ease of maintenance and maintenance (they do not “dry out” like inkjet), the possibility of color printing in color models of these devices. Thanks to the fact that in recent years the cost of these devices has decreased significantly, they are increasingly used and ordinary users at home.

First in the world matrix printer was released in 1964. But it was not initially used in computer systems, and for printing the exact time ⌚ in the design of Seiko watches.
Cm. .



This device, although practically not widespread among home PC users, turns out to be very valuable for those who constantly work with drawings or drawings in large formats. Like a printer, a plotter is capable of printing onto paper images made on a computer - drawings and drawings in very large formats (up to A0 format). Design and architectural bureaus are equipped with such devices; they are indispensable for printing large, demonstration diagrams, diagrams and drawings for various presentations.

The first models of plotters differed from printers in that they did not mix colors - they drew with “rapidographs” each filled with its own color. It was possible to select the thickness of the lines, but the color always remained one of the set installed in the plotter. Today, the latest models are completely free of this drawback.



Like the printer, the scanner is today one of the most popular devices for almost all PC users, both office and industrial, and home. It is designed for scanning (making a visual copy) of any images and saving them in digital form on any storage medium. Today's scanners, having evolved from slow and primitive devices, are today a model production technologies and scientific achievements.

Most models have impressive specifications, which determine the quality of the resulting copies:

  • Optical resolution. One of the most important characteristics that is directly responsible for the quality of the resulting scanning image. For modern models, this value can reach 11,000 dpi. True, you shouldn’t chase such parameters and shell out “extra money” if, for example, for high-quality printing on laser printer only 100-200 dpi and 96 dpi when displayed on a monitor are required;
  • Scan speed. Also an important value that allows you to significantly save time during processing. large quantity images. There are models in which this value reaches up to 80 pages per minute! Typically this indicator ranges from 1 to 3;
  • Scanner dynamic range. It has values ​​on a logarithmic scale from 0 to 4. In this case, the value “0” characterizes absolute transparency, and “4” - an absolutely black surface. For getting high-quality image photographs and other flat drawings require a density of 2. If you need to get a professional result, this value should be at least 3.2;
  • Optical density. A value characterizing the scanner’s ability to distinguish gradations of brightness. From a theoretical point of view, a 12-bit scanner is able to distinguish more gradations of brightness, but in practice this is not always the case. You can focus on the indicator of professional devices, which is equal to 3 units or higher;
  • Color depth. This is an indicator that tells you how many shades of colors this scanner model can distinguish. Today, there are devices that have this indicator equal to 24, 30 and 36 bits/pixel. For comparison, 24 bits is enough to distinguish 16.7 million colors. Interesting fact, the human eye is not able to distinguish between 24 and 32 bit images.

Structurally, all scanners are divided into:

  1. Manual. The image is scanned when a scanner is passed over it;
  2. Tablet. Great for home and office use when scanning both photographs and any other types of images;
  3. Leafy. Scanning is carried out by pulling the sheet through a special reading device. The parameters are similar to flatbed scanners;
  4. Drums, are used exclusively for printing purposes, as they have highly professional parameters and are very expensive.

Today, these devices are very popular among office and home PC users, since this peripheral device represents two (and in most cases) three devices “in one bottle” - a printer, a scanner and a copier. Of course, this is very convenient - it saves a lot of space on the table, and the cost of such a unit is significantly lower than the sum of these two or three devices.

The parameters of the MFP are identical to the parameters of the individual devices included in its composition, therefore, when choosing such a unit, you should focus sequentially on them, that is, evaluate the technical characteristics of the printing device (printer) included in the MFP, and then the scanner, and only after that make a decision. Sometimes similar devices may have excellent scanner data, but at the same time mediocre printing parameters.



For many years now, all motherboard manufacturers have included a sound card. That is, almost all PCs are capable of reproducing sound and music files, listen to music and watch videos with sound. In addition, as a rule, the motherboard also has audio inputs for connecting external devices - a microphone, tape recorder, external CD and DVD player, other sound-reproducing devices.

In order to take full advantage of this technical feasibility To reproduce sound, you must have either an active speaker system or headphones. An active speaker system is a pair of acoustic emitters (speakers) with a built-in or external sound amplifier.

Most modern models have a built-in amplifier right in the housing of one of the speakers, which on the one hand is convenient - saving money working space, on the other hand, such a design, of course, has rather mediocre sound characteristics compared to high-quality models, in which the amplifier, as a rule, is always external. But you should clearly understand that the “standard” sound codec built into the motherboard also does not have outstanding parameters, so in most cases the use of such speaker systems is quite justified.

For more or less high-quality sound reproduction using standard sound card You should select acoustics that have two (or better yet three) frequency bands and a power of at least 15-20 watts. In this case, we are not talking about listening to sound loudly, although the more sound power speaker system, of course, your speakers will sound louder, we are talking about the power reserve of your acoustics for more high-quality reproduction sound even when listening at minimum volumes. Of course, you can also purchase speakers that seem to have a “decent” output power, but at the same time the sound quality leaves much to be desired.

If the speaker system is intended to be used in the most minimal way (for example, for holding conferences on the Internet via Skype, working with applications, etc.), then, of course, in order to save money, you can buy a small pair of speakers that have only one , wide playback bandwidth. In this case, you can also think about purchasing headphones, complete with a microphone.

When choosing headphones, you should pay attention to at least three main parameters:

  1. Frequency range, which must be no worse than 20 Hz to 20 kHz;
  2. Active resistance, the value of which should be in the range from 16 to 32 Ohms. With lower resistance, the sound volume is higher, but keep in mind that the amplifier must be designed for low resistance;
  3. Sensitivity. This indicator directly determines the volume of the sound and should be no worse than 98-100 dB, otherwise, portable devices that do not have a powerful sound output simply will not be able to “pump up” them and the sound will be quiet.

Always pay attention to the material of the ear pads - they are directly adjacent to your ears, and this will determine how comfortable you will be when listening, especially for a long time.


If the microphone is intended to be used only for conferences and conversations over the network, then it makes sense to purchase a webcam, which, in addition to the camera itself, also has a built-in microphone. In this case, you can save not only on the work space near the monitor, but also money.



One of the currently popular peripheral devices designed for inputting video data into a PC and its subsequent processing - saving, transmitting, etc.

The main parameters that determine the quality of this device:

  • Permission. Defined in pixels. The higher the device resolution, the better picture quality will be obtained when entered into the PC. A size of 640x480 can be considered a good resolution, expensive models have a value of this indicator - 1024x960 and higher;
  • Matrix sensitivity. Very important parameter, which characterizes the ability to produce high-quality images at low lighting levels. To be fair, it should be noted that even the most expensive models also have interference when shooting in poorly lit areas;
  • Frames per second (fps). The higher this parameter, the sharper the image, especially if you are shooting fast-changing scenes. Good parameter A value of 30 frames and above is considered.

Most of the latest webcam models have a built-in microphone, autofocus, and backlight as additional functions. In this case, audio data is transmitted over the same interface as video data, which is very convenient - the number of connections to the PC is reduced, and the microphone input is freed up, which can be used to connect a professional microphone if necessary.

The webcam is connected to the PC via a USB port, and to obtain a high-quality image, the version of the USB port must be at least 2.0.

Modem



Modems have been used by personal computer users for many years to access the Internet. Previously, the connection was made through Dial-Up modems, the communication speed through which, as well as the quality, left much to be desired. The actual data transfer rate, as a rule, did not exceed 33.6 kBit/sec, and constant interruptions made it difficult to transmit or receive large files. Phone line at the same time she was also busy.

The emergence of xDSL technology radically changed the concept of data transmission over a copper pair, allowing users to reliable connection at speeds up to 24 Mbit/sec. towards the subscriber and up to 1 Mbit/s from him. This is realized using such a peripheral device - a standard ADSL modem.

In this case, the use phone number can be carried out simultaneously with PC operation via a modem. It is now possible to receive and transmit large files, conduct video conferencing in real time, and carry out group video broadcasting to a wide range of users (digital television).

Such a device is connected to a personal computer via Ethernet or USB port.

Game controllers


Computer peripheral devices also include game controllers – joysticks, gaming sets – “steering wheel-pedals”, and other devices.

They are connected to the USB port of a PC and are designed to simulate real control devices in gaming applications.


The device is made in the form of a regular pencil or pen, which fits comfortably in the hand and is connected to a PC via wired or wirelessly. It exactly copies all the user’s movements on a special mat or monitor screen, thus allowing you to draw in the usual way – by drawing. Besides, The “light pen” can successfully play the role of a manipulator like a computer mouse..

In comparison, a mouse does not allow you to draw in the traditional way, since its movements are difficult to coordinate. The light pen is completely free of this drawback.

Today, this device has gradually lost its relevance, since the emergence of touchpads - touch-sensitive panels - has made it possible to do the same thing, but without special devices connected to a PC. Computer drawings turned out to be more convenient to perform on another device - a “digitizer”.



It is a graphics tablet connected to a personal computer and designed to enter graphic data that the user writes or draws on its surface.

The convenience of the digitizer is that the image is visible not only on the large monitor screen, but also on the tablet itself, that is, it seems that the user is performing actions on a piece of paper.

The greater accuracy of modern models and ease of use have made this device very popular among its creators. animation graphics– creators of modern cartoons, computer games, architects and designers, computer artists.

What's happened peripherals computer or just peripherals? Peripherals are devices that connect to a computer and expand its functionality. Unlike a computer (, ...), their presence is not necessary for the computer to work. For example, a printer is a peripheral device used to print information. The computer will work without a printer, but not without a processor. Because The processor is a mandatory PC device.

The most popular computer peripherals are and. It seemed that the keyboard and mouse were mandatory devices, without which it would be impossible to work on a computer, but this is not so. Operation will be impossible for the user, while a computer without these devices will turn on, boot and wait for commands entered using the keyboard or mouse. Let's look at some popular devices.

Headphones and speakers are the next most popular peripheral devices. In itself there is only a small speaker, used mainly to signal errors at boot time. To fully listen to sound, speakers or headphones are required.

– another peripheral devices. Serve for long-term storage of information.

Printer and scanner are peripheral devices designed to print information (printer) and obtain a digital copy of an object (scanner). In home computers, a scanner is mainly used to digitize text and photos. Most often, these two devices are combined into one housing. Such a device is called an MFP - a multifunctional device.

In addition to the above popular devices, there are quite a lot of computer peripherals for various types of tasks.

At first glance, laptops and PC monitors have some advantage over television equipment in matters of connection. However, modern televisions equipped large set connectors, so connecting your computer to your TV is much easier than it seems. Variety of interfaces The reality is that the compatibility of a computer and a TV depends on the degree of wear (age) of the older device. If you leave home today [...]

The printer can rightfully be considered one of the most important office equipment in everyday life. regular user. Indeed, with the help of a printer you can print out abstracts, term papers, scientific papers, family photographs and much more. Depending on the cost of the device, the printer can perform various functions, for example, printing on professional photo paper, using a wider color palette, etc. […]

Computer speakers are a peripheral device and are designed to output sound. For a home computer, the presence of speakers is a prerequisite, because... Without them, it is impossible to fully watch a movie, listen to music, or play games. For an office PC, the lack of acoustics is still somehow justified, but it is already impossible to imagine a home computer without them. What types of computer speakers are there? Almost all speakers […]

After turning on the scanner, you must install the driver for this device so that data can be transferred between the computer and the scanner. Start by connecting the scanner to the port Computer USB. (Read your scanner's manual to find out how to connect it to your computer.) Turn on the scanner. Many scanners use plug and play technology, which allows Windows to recognize the hardware and install […]

A scanner is used to transfer text and images from paper to a computer in file form, which is the reverse of printing on a printer. Previously they were common hand scanners, which had to be smoothly moved along the sheet being scanned. In addition to being inconvenient to use, their big drawback was that due to the uneven speed of movement, the resulting image was elongated or, conversely, […]

Peripheral devices of a personal computer are all equipment that simplifies the interaction between the user and the computer.

In fact, the only elements of a PC that cannot be called its “peripherals” are the RAM.

First of all, because they represent the computer itself, and also because they can be used without a chipset or motherboard computing device impossible.

While without the rest it is quite possible to do this - without a monitor, and without a video card, and even without hard drive(when replacing it with another drive), the system will start, although it will not be able to interact with a person.

By location, all PC peripherals can be divided into two groups:

  1. Internal devices, installed inside system unit. These include built-in drives for reading disks, hard drives and solid state drives, video cards and even microphones and, if we are talking about laptop elements;
  2. External hardware located outside the computer. Among such devices you can also find floppy drives and hard drives - but only those connected externally. External peripherals are called both, and, and input devices such as keyboard and mouse.

Another classification option is by purpose.

All peripheral devices can be divided into three categories - peripherals for input (pointers, keyboards and scanners), output (display and printer) and data storage (and other types of drives).

Input Devices

Input peripherals are equipment intended for entering data into an electronic computer. There are several types of such devices:

In addition, there are separate devices for inputting graphic and audio information.

And also pointing (coordinate) and gaming - while, for example, joysticks are classified as both the first and second types.

While gamepads and steering wheels are only for devices intended for games.

Rice. 2. Basic devices for entering information into a computer.

Keyboards and pointing devices

Computer mice are designed to control the cursor and issue commands to the computer using keys and wheels located on the manipulators.

Keyboards allow you to do the same by mechanically entering characters.

Modern operating systems practically cannot work without these devices - except for all-in-one PCs with touch screens.

And to connect them, three connector options can be used (outdated Com port, more modern PS/2 and universal USB).

Although some models can connect to PCs (primarily laptops).

Certain types of coordinate peripherals for input include gaming devices - steering wheels, joysticks.

And even special dance platforms and light guns. The same list also includes a trackball, the operating principle of which is reminiscent of a computer mouse.

Rice. 3. A game controller that combines the functionality of a keyboard, gamepad and tablet.

Transmission of sound and graphic information

To simplify the entry of graphics, there is special type peripheral devices – graphics tablets.

With their help, you can transfer information to a PC by drawing on a surface, like on paper. The use of these peripherals is important for developing drawings and creating design projects.

In order to transfer a ready-made image and even text onto a PC, they use .

Scanners can be black and white and color, hand-held and desktop (which, in turn, are divided into roller and flatbed).

You should know: A flatbed scanning device allows you to scan any flat image - from a book, from a sheet of almost any size (if the formats do not match, scanning is carried out in parts). The roller version provides continuous scanning, but is only suitable for sheet materials.

Rice. 4. Scanning flatbed device.

To transfer information to a PC in the form of video recording, use web cameras connected to the system unit via USB or wirelessly.

They are also suitable for communicating over the network.

The camera can be equipped to record not only images, but also sound.

If this option is not provided, recording should be done using an external device.

Rice. 5. Webcam with 1080p resolution.

The need to use microphones arises when transmitting audio information and there are no built-in options typical for laptops.

However, even to mobile computers Sometimes it is necessary to connect an external device via a special 3.5 mm jack. For example, to get more high-quality sound.

Gaming devices for output include helmets, although they can be used not only for games.

Rice. 7. Peripherals for information output.

Output of graphic information

The main device for outputting graphic information from a computer is a video card. With its help, data can be converted into a static image or video.

Rice. 8. External video card with two coolers.

The video card transmits the image to the monitor, which consists of a screen, a power supply and several control boards.

To connect this peripheral device to a PC, different ports located directly on the graphics card:

  • on older computers – ;
  • on more modern ones - DVI;
  • at the most latest models– and DisplayPort.

Rice. 9. Types of connectors for connecting a monitor.

You should know: The difference between monitors and TVs is the absence of speakers (although some models have built-in speakers). Therefore, you can use them to receive a television signal only if you have a tuner on your computer (video card). At the same time, most TVs can be used as monitors.

To enlarge the image transmitted from the computer, peripheral devices such as projectors are used.

With their help, a picture or video is projected onto any flat (and, preferably, plain and light) surface.

Some projector models have built-in speakers and a card reader for reading information from external media, although most require a connection to a computer via USB, video input, or even Wi-Fi to operate.

There are also projection devices that support 3D technology.

Rice. 10. Compact projector with USB connection.

While the top versions are practically full-fledged computer– even with installed operating system.

Rice. 11. AIO VR Sky CX-V3 virtual reality glasses with Android OS 5.1.

Peripherals intended for static output of images include printers (and their special case, plotters).

With their help, text or a picture is applied to a solid medium - paper or film.

More modern devices allow you to get not a flat, but a three-dimensional image.

Peripherals are connected to the computer either using special ports (LPT1), or through universal connector USB, or wirelessly.

Rice. 12. Compact home printer for 3D printing.

Audio output

Speaker systems are used to convert information into an audio signal.

These include speakers that are practically mandatory attribute modern desktop computer, as a rule, not equipped with built-in speakers.

Laptops do not require external devices due to the presence of their own speakers.

However, to increase volume and sound quality, even mobile computers can be connected (via a 3.5 mm connector or, in rare cases, via USB) to external speakers.

You can do without an additional speaker system even when used as a monitor.

However, to transmit sound to only one user (in order not to disturb other people), you should use their smaller version - headphones.

Devices are connected to a desktop PC via standard connector.

Moreover, some models can also be equipped with a microphone, which makes them more convenient for communicating over the network or recording sound.

Rice. 13. Speakers and headphones.