Internal peripherals. Functions of the main and peripheral devices of a computer

Computer peripherals are non-core components of a computing system. Without them, the ability to perform basic functions remains. So, if the modules connected to the motherboard RAM, video adapter, power supply are indispensable components, That peripherals PC ( personal computer) belong to the auxiliary group.

To clarify, let's use an analogy, comparing a computer with a person. PCs can be compared to hands and feet: they significantly expand the range of tasks that can be solved. In this regard, computers benefit, since if there are interface ports, you can connect any existing technical solutions, doing computer system universal.

Depending on the purpose, the following classification of peripheral devices is used:

Data input/output solutions;

Devices for information storage needs;

Devices for exchanging digital (or analog) streams with other components.

Let's take a closer look at each group.

PC peripherals designed for data input are deservedly headed by the mouse and keyboard. The latter is a set of buttons, pressing each of which corresponds to a specific one. It is with its help software part The computer knows exactly what was pressed, including various combinations.

The modern keyboard is far from ideal, since the hands get tired after prolonged use, the placement of symbols on the buttons is not optimal, and the mechanism for returning the pressed key is not always properly configured. Almost all manufacturers offer improved models that take the above features into account. However, they have too high cost, which does not allow such solutions to occupy their niche in the mass market.

Depending on the connection method, there are wired and wireless devices. This group also includes gaming joysticks, pedals and steering wheels, light guns, steering wheels for flight simulators.

The mouse type manipulator became widespread after its popularization in operating systems elements of which are convenient to control not with buttons, but with a pointer. Currently, there is a gradual displacement of classical wired solutions more convenient, communicating with the computer via radio frequencies.

Information entry and digitization is also carried out by scanners. These devices can be part of an office combine - MFP, which combines a printer and a scanner in one housing.

There are not only stationary, but also manual solutions, which in some cases turns out to be very convenient.

Without the ability to display the results of work, the computer would be a “thing in itself” - a kind of black box, completely useless. There are various main ones of which is the monitor. Without him full-time job not possible with a computer. Depending on the principle used for drawing a picture, a distinction is made between CRT and LCD solutions.

In addition to forming an image on the screen, by connecting a printer, you can be able to output data to paper or other similar media.

PC peripheral devices of the second group perform the functions long-term storage digital data. These are hard drives, CDs, streamers (media - tape), disk drives and flash drives.

Data exchange is carried out by modems and

Peripheral devices include: printers, scanners, acoustic speakers, modems, i.e. those devices without which the computer can function independently.

Printers. Printers (print - printing) are automatic printing devices designed for printing the results of work on a computer (texts, drawings, graphs) onto paper. Based on the principle of operation, impact-matrix, inkjet and laser printers are distinguished.

Impact matrix printers print using a head with a set of needles. The number of needles in the head can be different - 9, 18 and 24. The movements of the needles, head and sheet are controlled by electronic circuit printer in accordance with commands coming from the computer. At the command of the computer, the needles are assembled into groups corresponding to the outlines of the letters, and, moving out of the head, beat out the desired symbols through the ink ribbon. The more needles in the head, the higher the print quality. Printing speed is from 60 to 10 seconds per page.

The advantages of dot matrix printers include their cost-effectiveness. Price consumables for them the lowest, and the dot matrix printer itself is inexpensive. Other advantages of dot matrix printers are determined by the impact principle of operation, which allows you to print several copies at once using special self-copying paper. The advantages of matrix technology include the ability to print on materials with non-standard sizes. This can be rolled paper, cardboard and even passports and passbooks.

The disadvantages of dot matrix printers include relatively low speed printing and unpleasant noise during operation. On dot matrix printers it is impossible to do much color printing.

In inkjet printers, the image is formed by microdroplets of special ink different colors, which are ejected through the nozzles in the print head. Up to a million droplets are released in one second. This allows you to use any paper for printing, including cardboard.

Inkjet printers are the most popular of all types of printers. To the advantages inkjet printers include:

Low price(3 times lower compared to laser printers);

Low noise level compared to dot matrix printers;

Cheapest color printing.

A good inkjet printer can print not only text materials, but also documents with color photographs and diagrams.

The disadvantages of inkjet printers include:

Instability printed text to the action of water, light and friction;

The need to use special security paper to obtain color images;

Despite the relative cheapness of the printer, its operation requires serious expenses due to the frequent replacement of expensive cartridges.

Repairing the print head costs an amount almost equal to the cost of the printer itself;

Laser printers use a laser beam to print. The printer has a drum roller coated with a semiconductor substance that can become electrified when irradiated with a laser. Mirror scanning causes a pulsating laser beam to slide along the lines along the drum. Flashes of the beam occur in those places where the image of the dots should be.

The smallest particles of dry paint (toner), which is located in the container under the drum, are attracted to the areas electrified by the laser. Then the roller is rolled over a sheet of paper, and the paint transfers to it. Fixing the image on paper is carried out by melting the toner with a special drum-oven.

Laser printers provide the fastest printing speeds of any printer and do not require special paper.

The disadvantages of laser printers include their high cost and high power consumption. It is not recommended for use in an apartment due to large quantity ozone, which it emits during operation. Ozone is an oxidizing agent and, in overdose, is harmful to health.

Scanners. A scanner is a device that allows you to enter images of texts, drawings, photographs directly from a paper document (Fig.) into a computer.

Rice. Scanners: Left - roller; on the right - tablet; below - manual

Scanners are classified according to the color of the input images into black-and-white and color and according to the method of use - into hand-held and desktop.

Hand-held scanners are the simplest in design: they are moved manually across the image. Desktop scanners are divided into flatbed and roller scanners. Flatbed scanners the most common; They allow you to scan both sheet-fed and bound (book) documents. Roller scanners are the most automated, but the documents being scanned should only be sheet-fed.

Computer speakers. The built-in signal speaker in the computer is not designed to provide high-quality sound, so acoustic speakers are used to listen to music recordings. The principle of their design is similar to the device speaker systems for household audio equipment. Depending on the type of amplifier, active and passive speakers are distinguished.

For passive speakers Signals are amplified by an amplifier located on sound card inside the system unit. In this case, the analog signal is exposed to numerous electrical interferences, which leads to acoustic distortion.

IN active speakers the amplifier is located in one of the speakers (outside the system unit), which helps improve sound quality.

Modems. A modem is a device for exchanging information with other computers via telephone network. It connects the computer to the phone. The term "modem" is formed from two words (MODULATION-DEMODULATION). The modem modulates and demodulates information, i.e. converts digital signals computer into analogue ones, compatible with the phone connected to it and, conversely, accepts incoming calls from the phone analog signals and converts them into digital ones compatible with the computer connected to it. A modem is required to connect to electronic networks Internet and for working with by email.

A fax modem is a modem for sending and receiving images. The sequence of operation of the fax system is as follows: optical scanning of the image, modulation and transmission of signals via communication channels, demodulation and making copies. Majority modern modems are also fax modems.

Sources uninterruptible power supply. If there is a sudden change in voltage parameters or complete shutdown electric current data contained in operating memory computer may be irretrievably lost.

Therefore, when selling a computer, an uninterruptible power supply (UPS) is always offered. The UPS includes battery, which is constantly being recharged and in the event of a voltage drop, its energy is used to power the computer for 15-20 minutes for crash work.

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 using it once before mechanical mouse. It was necessary to forcefully drag across the mat to move the mouse cursor to right place desktop. There are regular cheap mice and special fancy gaming mice. I have a big rug and a play area at home. laser mouse, which at that time was bought for 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 with 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 sound card. Mostly they are built into the motherboard.

If you have good speakers, there are 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 motherboard or buy 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 at the moment Probably in all major cities they use it high speed internet, via ADSL modems, dedicated VPN channels, wireless Wi-Fi and others.

Webcam

A web camera 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 storage devices include small devices, which store information from a flash drive 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. At USB hard drives The storage capacity is of course larger.

Printer

A printer is needed to print out 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

Uninterruptible power supplies or rectifiers AC 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 to 10 minutes.

Joysticks and game controllers

Using joysticks and game controllers you can comfortably play various games 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.

Computer Peripherals | 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

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 popular devices listed above, 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 are equipped with a large set of connectors, so connecting a computer to a 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 technicians 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, print on professional photo paper, use a wider color palette etc. […]

Computer speakers are a peripheral device and are designed to output sound. For a home computer, having speakers is 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 imagine without them home computer is no longer possible. What types of computer speakers are there? Almost all computer speakers […]

After turning on the scanner, you must install the driver for this device so that it becomes possible transfer data 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, […]

External, or peripheral, devices are components of a personal computer that are located outside the system unit. They are used only at a certain stage of the information processing process. First of all, these include devices that record output results: a printer, scanner, modem, various external drives, etc. It is worth noting that the very concept of “computer peripherals” is quite arbitrary. So, for example, this can include external DVD drive, since it represents independent block and connects to the system unit using special cable. And vice versa, internal modem is an expansion board, located in system unit and cannot be classified as peripheral equipment. The term “peripheral” itself refers to devices that connect the computer and outside world(devices that are used to both input information into a PC and output it). The list of this equipment is, in principle, unlimited. Interestingly, monitors are not included.

Peripheral devices are divided into:

• basic ones, which are a mandatory component for normal operation computer;
• others used as needed.

Main types of external equipment

This type includes devices that control the cursor, and partly modems (in the case of a terminal or diskless station). In principle, almost any equipment capable of generating electrical impulses or be controlled by them. Peripherals are connected to the PC using external interfaces or specialized adapters and controllers, which are a means for connecting equipment to the computer bus. Remember that you should distinguish between the meanings of the concepts “controller” and “adapter”. Yes, they are both used for pairing, but the controller is capable of performing independent actions after it receives a command from the program that controls it (some particularly complex ones even have their own processor).

The following types are currently widely used hardware, designed to interface the computer core with external equipment:

Classification of external equipment

Peripheral devices, depending on the functions they perform, are divided into the following types:

• for entering information: keyboards, mice, trackballs, etc.;
• for outputting information: printers (matrix, inkjet, laser);
• for storing information: external drives, CD and DVD drives, hard drives, streamers;
• for information exchange: modems, fax modems.

Separately, it is worth mentioning uninterruptible power supplies, designed to save information and correctly shut down work in the event of a power outage.

Conclusion

As you can see, external PC devices have become an integral part of any information system. They collect, store, search, transmit and process data. Each specialist has huge selection auxiliary devices for solving a variety of tasks.