The most important element of a computer is memory. It is divided into operational and long-term. Memory is measured in bytes. One byte can store one letter or number. Kilo bytes (KB), megabytes (MB) and gigabytes (GB) are also used. One kilobyte is equal to 1024 bytes. Due to the fact that the computer uses a binary number system, such numbers are more convenient than round ones. Access to RAM takes almost no time from the processor, this memory is always less than we would like. The capacity of long-term memory is much larger, but it takes quite a lot of computer time to access it.
A bus system is a tool that allows data flows to pass between components, eg. The operating system is designed to allow the user to control the computer and send commands to the central processing unit. It acts as an interface between the user and the computer. What is considered part of the central division depends on the context. Thus, the 5 components mentioned should represent a good average surface.
The software mainly expands the functionality operating system. Strictly speaking, the operating system is also software, but has a higher priority role. For example, there is no operating system Writing letters or editing images. It means that software must adhere general conditions provided by the operating system. If, for example, it is necessary to initiate certain things that the operating system does not allow or understand, then this is not done systematically.
Next important element computer - display controller, or video adapter. Its task is to convert the digital signals from the microprocessor into a video signal supplied to the display. The video controller has its own memory, the size of which determines how many dots the image on the screen can be divided into, and how many colors can be used. The most common currently are VGA and SVGA video adapters.
A computer. Purpose and principle of operation
Therefore, software must always be compatible with the operating system and in almost all programs, compatibility is indicated. The operating system and software are not physically present, but only in the form of data. They must be available for the processor to work with and therefore loaded into main memory because the processor communicates directly with main memory due to its speed. This the only way make sure processing is fast. When using disk as memory, the results will be much slower.
VGA provides image formation from 480 lines of 640 dots each, and only 16 colors can be used simultaneously (640X480X16 mode). SVGA - adapters, depending on the amount of memory installed on them, can operate in more modes, for example, 800x600x256, 1024x768x256 and even 1600x1200x16M. Of course, the smaller the dots that make up the image, the easier it is for the eye to perceive it.
The operation of a computer, shown schematically. The image does not show the mode of operation of the central unit adequately. In translation, this roughly means "random access memory." Data can be stored anywhere in main memory. Inputs can be made through input devices. First, the operating system takes the data streams sent by the input devices and sends them, as it were, using the software. Depending on how the software is programmed, certain calculations are required depending on the data flows.
There are several types of computers that differ in the composition and characteristics of their components, which are used to solve various problems. So, to solve complex problems of information processing, a computer is required that would contain the most powerful device for performing calculations. In it, as a rule, the qualitative presentation of information is not essential, and the device on which this information is displayed can be very weak. Typically, computers that meet these conditions and work in the general computer network of the office are called servers and are designed to process information on the requirements coming from other computers. On the other hand, a computer designed mainly for printing documents may not have such a powerful information processing device, but a printing device often of a fairly high quality must be connected to it. Offices use computers that are permanently located at workplaces.
To do this, certain commands are sent to the operating system. When the operating system understands the instructions and allows execution, the instructions are passed to the processor. The transfer to the processor is not in human-readable language, but in machine code. That is, the processor receives instructions as binary numbers with 0 or so, the so-called data stream is passed to the processor. The operating system ensures that data streams also contain "correct" zeros or ones.
The processor has a control unit and an arithmetic unit. The control unit provides coordination of commands. Because not all commands need to be executed at the same time, but in a logical order. The actual processing is done in the calculator. The arithmetic block calculates the data that is retrieved from the main memory.
The basis of the personal computer is system unit. It organizes work, processes information, makes calculations, provides communication between a person and a computer. The user is not required to thoroughly understand how the system unit works. This is the lot of specialists. But he must know what functional blocks the computer consists of. We do not have a clear idea of the principle of operation of the internal functional blocks of the objects around us - a refrigerator, a gas stove, a washing machine, a car, but we must know what is the basis for the operation of these devices, what are the capabilities of their constituent blocks.
The result is sent back to the output device in machine code. This often requires transformation. Because, of course, people don't want a data stream of all zeros or ones, but screen output, speakers, and so on. So he sees or hears something. The graphic card has the job of doing that conversion and converting the digital signals to analog signals so that something can be displayed on the screen at the end. Sound card also converts digital signals to analog signals, except that the output is in audio form, such as through speakers or headphones.
The system unit of a personal computer consists of a motherboard measuring 212/300 mm and located at the very bottom, a speaker, a fan, a power supply, and two disk drives. One drive provides input-output information from a hard drive, the other from floppy disks.
The system board is the central part of the computer and is made up of several dozen integrated circuits for various purposes. The microprocessor is made in the form of one large integrated circuit. A socket is provided for an optional Intel 8087 microprocessor - floating point operation. If you need to improve the performance of your computer, you can place it in this slot. There are several modules of permanent and random access memory. Depending on the model, from 5 to 8 slots are provided, where boards of various adapters are inserted.
A common question is why a processor can only process instructions and data in binary. The answer is logical and simple. The processor is an electronic element and therefore knows only two states. Man knows the 10-state decimal system because he has 10 fingers. Imagine that a computer has only two fingers and still wants to count on it and is able to do so. The representation of numbers is just different.
The functional principle of the computer was developed by the Hungarian mathematician John von Neumann. The commands are executed one by one, step by step. Commands and data are retrieved from memory by the controller. This can quickly lead to bottlenecks when data is loaded from memory and at the same time new instructions must be loaded in order to make optimal use of the calculator. This is why one speaks of von Neumannschen's "bottleneck". Advanced computer architecture is a very simple model. Compared to the von Neumann calculator, this presentation has been extended by several important system components.
An adapter is a device that provides communication between the central part of the computer and a specific external device, for example between RAM and a printer or hard drive. The board also installs several modules that perform auxiliary functions when working with a computer. There are switches that are necessary to ensure the operation of the computer with the selected composition external devices(computer configuration).
Main Processor
Hence the term "extended architecture". It's about bringing the computer closer to reality. The main processor is the central element of the computer. The main processor is the functional unit of a computer that provides real computing power. He is responsible for the processing of information and control over its processing. To this end, the main processor retrieves instructions one by one from memory and initiates information processing.
The clock will switch to the whole system. The system clock is generated centrally by clock and synchronized with different multipliers at different clock speeds. Including the main processor and system bus. The system bus is a line on which occupancy and signal levels are defined. Various components are connected to it, which can communicate with each other or with the processor. Computer systems usually have several different bus systems through which all components are connected in some way.
CPU occupies a central place in the structure of the computer, as it automatically controls the interaction of all devices that make up the computer and performs arithmetic and logical operations.
Inner memory is a memory of high speed and limited capacity. In the manufacture of a memory block, either electronic circuits on semiconductor elements or ferromagnetic materials are used. Structurally, it is made in the same package with the processor and is the central part of the computer. Internal memory can consist of RAM and permanent memory. The principle of its division is the same as that of a person. We have some information that is stored in memory constantly, and there is information that we remember for a while, or it is needed only at that moment while we are thinking about solving a problem. RAM is used to store the operational, often changing in the process of solving the problem. When solving another task, only information for this task will be stored in RAM. When the computer is turned off, all information in the RAM is in most cases erased. Permanent memory is designed to store permanent information, which does not depend on what task is being solved in the computer. In most cases, constant information is programs for solving frequently used problems, for example, calculating the functions sinX, cosX, lgX, as well as some control programs, microprograms, etc. Turning off the computer and turning it on does not affect the quality of information storage.
Input and output block
A simple bus system includes an address bus, a data bus, and control lines. Devices connected to the input and output are called peripherals. Like keyboard, screen, mouse, printer and scanner. Sensors, converters, power amplifiers and actuators. Hard drives and removable drives are not typical input and output devices. They are related to data warehouses.
Data stores are components that can permanently store programs and data. These include hard drives, removable storage and related drives, and solid-state storage devices that can retain their data even without power.
External memory is designed for long-term storage of information, regardless of whether the computer is running or not. It is characterized by lower performance, but allows you to store a large amount of information compared to RAM. Information is written to external memory that does not change in the process of solving a problem, programs, solution results, etc. Magnetic disks, magnetic tapes, magnetic cards, punched cards, punched tapes are used as external memory. Input-output devices are designed to organize the input of information into the computer's RAM or the output of information from the computer's RAM to external memory or directly to the user (NML - magnetic tape drive NGMD - floppy disk drive, NMD - hard disk drive, UPC - input-output device from punched cards, UPL - input-output device from punched tapes).
Overview: Computer Architecture Components
Customer Opinion: The Basics computer technology written in a really understandable way, no ballast and an excellent reference book. All in all, a highly recommended book. The customer's review has been automatically translated from German. But so far this fantastic device exists only in the minds of physicists. Huge prototypes in the laboratory are concrete, but this already serves as proof of the principle of the invention: in a quantum computer, the processor, the "brain" of the machine, does not consist of chips, as in conventional models, but atoms that interact with each other to interpret information and execute calculations.
Monitor something like a TV. But TV cannot be watched close up, because it is very harmful to the eyes. The monitor also affects the eyes, but not as much as the TV. When working with a computer, we get most of the information by looking at the monitor screen. The image of the monitors is clearer. Monitors are different. They differ in screen sizes and image quality. Screen size is measured in inches. The length of half a match is an inch. Measure the screen obliquely - between opposite corners. Regular monitors are 14 inches. Often there are also monitors with a size of 15 inches. Much better monitors, which have a size of 15 inches. They cost more, but their quality is higher. You can work with such monitors without a protective screen, although it will not interfere with them either.
This is of great importance: on a traditional computer, all image, sound and programming data is converted and interpreted as giant sequences of 0s and 1s, so-called bits, the basic unit of digital information. Who is this numerical reading, these are transistors, small electronic devices, which make up the processor and memory chips. The problem is that each transistor only interprets one bit at a time. But if we change the chips to atoms, everything changes. The superposition principle of quantum physics states that a particle can be both 0 and 1 at the same time.
Keyboard every computer has. With its help, information is entered into the computer or commands are given to the computer. The great-grandmother of the computer keyboard was the typewriter. From her, the keyboard inherited keys with letters and numbers. But a computer can do more things than a typewriter, and therefore its keyboard has many more keys. Different keys serve different purposes. For example, an ordinary typewriter does not have keys for erasing what is written, but a keyboard does. Such a typewriter cannot insert a new word between two others, but a computer can, and there is also a special key for this. When we play computer games, we most often use the arrow keys. They are also called "cursor keys". Using these keys, you can control how the hero of the game runs around the screen. Very often in games, the STRI and ALT keys are used. The hero shoots with one key, and jumps with the other. These are quite large keys, besides, they are located at the very bottom of the keyboard, and therefore they are convenient to use. The longest key is SPACE. It can be pressed even blindfolded. And because it is also very often used in games.
This function allows you to do calculations simultaneously, with several bits being interpreted at the same time. So far, most researchers have been able to assemble processors with less than ten atoms. The business model must take decades to reach stores. There is no faceless invention. So far, no one knows what this visionary technology will look like.
The secret is to use atoms instead of chips to read the information transmitted, for example, in the form of light beams that change the polarization of the atoms. Each particle stores multiple data at the same time. Since the interaction between atoms is fragile, all interference must be forbidden. The prototype becomes huge. It cannot determine if a quantum computer will have a screen, keyboard, and mouse, as modern models. Since scientists are more interested in developing a processor, the results of atomic computing are read into technical devices such as voltage and current meters.
Mouse- a very convenient plastic machine to control the computer. This is a small box with a rubber ball spinning inside. When the mouse moves on the table or on a special mat, the ball spins, and the mouse pointer moves on the screen - the cursor. Like the keyboard or joystick, the mouse is used to control the computer. It's like a keyboard in reverse. The keyboard has more than 100 keys, and the mouse has only 2, but the mouse can be rolled around the table, and the keyboard stays in one place. The mouse has buttons. Usually there are two of them - the right button and the left one. On left button comfortable to press with your index finger. Therefore, this button is used very often. Right button used less often - when you need to do something very cunning or smart. Between the two buttons there is a small wheel for scrolling or, as they say, for quickly viewing printed material.
Quantum computers should optimize data retrieval. In an unordered list of 144 names, the traditional model performs an average of 72 operations until it finds the correct one, which is the total number of names divided by two. A quantum device only needs 12 search queries or the square root of the common.
Operating control devices
Personal computers have components such as graphics cards and processors that are hotter at work. That is why computer boxes also have a fan cooling system. They are especially useful for machines that boot up for long periods of time.
a printer- This is a separate device that is used to display on paper the information available in the computer. It connects to a computer using a USB connector. The very first computer printers were inkjet and printed very slowly. The typed text was similar to that produced by typing on a typewriter.
Fans remove hot air that accumulates inside the outdoor system. It then sucks cold air from the outside environment used to cool the components. The implementation of this project requires very simple preparation. Of course you need a PC. To get to it, a set of screwdrivers will help you. The fans you are about to receive should be the same size as those used in the computer system.
Remember to always turn off the power when using the equipment. This will prevent the computer from short circuiting, which could damage the computer. Besides, you will be safe. You need the strength of the fans. Computer fans have an internal electric motor. It connects to a power supply or motherboard. Power is provided by three or four pin connectors. The motherboard or power supply sends an electrical charge in the form of voltage to the fan motor.
The most popular printers today are laser printers. They produce pages that are not inferior in quality to book pages.
Scanner- it's like a printer "on the contrary." Using a printer, a computer prints texts or pictures on paper. And with the help of the scanner - on the contrary. Texts or pictures printed on paper are entered into a computer for storage and for later use. Scanners are used by artists to draw objects for computer games. However, artists do not like to use them very much. They like to draw with a pencil on paper - it turns out better and faster. Therefore, pictures for games are first drawn with a pencil. The image is then entered into a computer using a scanner. So the drawn picture is converted into data that enters the computer. The picture is colored on the computer. Used for coloring graphics editor. Although the graphics editor is not very convenient for drawing, it is very suitable for coloring. An artist needs a scanner just like a printer needs a writer.
PRINCIPLES OF ORGANIZATION AND WORK OF PC
Introduction
Exercise 1
1. Principles of organization and operation of a personal computer
1.1 Internals of a personal computer
1.2 External devices of a personal computer
1.3 Classification and characteristics of computers
2. Architecture of a personal computer
2.1 Principles of building a PC
2.2 Fundamentals of the doctrine and structure of the first generations of computers
3. Central processing unit
3.1 CPU functions
3.2 Operating devices management
Conclusion
Task 2
Task 3
Task 4
Bibliography
INTRODUCTION
In the second half of the 20th century, mankind entered into new stage of its development. During this period, the transition from an industrial society to an information society began. The process that ensures this transition is called informatization. INFORMATION – it is a process of creation, development and general application information media and technologies that ensure the achievement and maintenance of the level of awareness of all members of society, necessary and sufficient for a fundamental improvement in the quality of work and living conditions in society. At the same time, information becomes the most important strategic resource of society and occupies a key place in the economy, education and culture.
The inevitability of informatization of society is due to a sharp increase in the role and importance of information. The information society is characterized by a highly developed information sphere, which includes human activities in the creation, processing, storage, transmission and accumulation of information.
The scientific foundation of the process of informatization of society is a new scientific discipline - informatics.
In this paper, the following issues will be considered: the principles of organization and operation of a personal computer, the architecture of a personal computer, the device of the central processor.
1. PRINCIPLES OF ORGANIZATION AND OPERATION OF A PERSONAL COMPUTER
The PC includes the following main devices:
· system unit;
Monitor
· keyboard;
In addition, additional devices can be connected to the PC, called peripheral (external), which can be divided into several groups.
Input devices: scanner, digital camera, graphics tablet.
Output devices: printer, plotter.
Control devices: trackball, contact pad, joystick.
Devices that simultaneously perform the functions of input and output of information to / from a PC: modem, sound set-top box, network card.
Let's consider the purpose and composition of the named components of the Personal Computer, and first of all the system unit.
There are two buttons on the front (or front) side of the system unit:
· power button. It is her who is pressed, turning on the computer and turning it off after the work is completed.
The Reset button is designed to restart (reboot) the computer
Drives. In addition, on the front panel there are necessarily several devices that work with removable media - disk drives. The main, larger drive is designed to read compact discs of various formats - CD - ROM, DVD or Blu-Ray. In older system units, you can find a small floppy disk drive with a capacity of 1.44 MB, but today this is a rarity.
The front panel of most modern system units has several connectors for connecting external devices. As a rule, the panel with connectors is located at the bottom of the system unit. Here you can find one or two universal USB connectors, a square jack for a high-speed FireWire port, and a round headphone jack. When looking at the system unit from behind, it is easy to get confused in the numerous sockets and connectors designed to connect external devices. Small round connectors are designed to connect a microphone, headphones and speakers. The PS/2 ports are for connecting a keyboard and mouse. IEEE 1394 (FireWire). This high-speed port is for connecting external devices with high data transfer rates, such as digital video cameras or external storage devices. The LAN connector is for connecting to a local network.
1.1 Internal organization personal computer
CPU.
One of the main devices of a modern personal computer is a processor. Which, at first glance, is simply a silicon crystal grown using a special technology. However, this crystal contains many individual elements - transistors, which together give the computer the ability to "think".
Currently, there are many firms for the production of processors for personal computers. These are Intel, AMD, Cyrix, VIA, Centaur/IDT, NexGen, and many others. However, the most popular are Intel and AMD. We will try to consider the development of the processors of these leading companies. However, before delving into the history of processor production, it is necessary to characterize some of the technical terms that characterize the processor.
The clock frequency is the speed of the processor, namely the number of operations performed within 1 second.
The main functional components of the processor
Core: The heart of the modern processor is the execution module. The Pentium has two parallel integer streams, allowing you to read, interpret, execute, and send two instructions at the same time. Branch Predictor: The branch predictor tries to guess which sequence will be executed each time the program contains a conditional branch so that the prefetch and decode devices get the instructions ready beforehand. floating point block. Third execution unit inside the Pentium, performing non-integer calculations Primary Cache: The Pentium has two 8kb on-chip caches, one each for data and instructions, which are much faster than the larger external secondary cache. Bus interface: takes a mixture of code and data into the CPU, separates them until ready for use, and reconnects them, sending them out.
Table 1
Comparative characteristics of video boards.
| 88006TX | 8800ST8 | 79006TX | 7800OTH | |
| Process technology, nm | 90 | 90 | 90 | ON |
| Number of transistors per core, million | 681 | 681 | 278 | 302 |
| Vertex block frequency, MHz | 1350 | 1200 | 700 | 470 |
| Core frequency, MHz | 575 | 500 | 650 | 430 |
| Memory frequency, MHz | 900 | 600 | 800 | 600 |
| Effective memory frequency, MHz | 1800 | 1200 | 1600 | 1200 |
| Number of vertex blocks | 128 | 96 | 8 | 8 |
| Number of pixel blocks | 128 | 96 | 24 | 24 |
| Memory bus width, bit | 384 | 320 | 256 | 256 |
| Memory size on OP11, MB | 768 | 640 | 512 | 256 |
| GPU memory bandwidth, GB/s | 86,4 | 48 | 51,2 | 38,4 |
| Number of vertices/s, million | 10 800 | 7200 | 1400 | 940 |
| Pixel bandwidth, number of ROPs x frequency, billion/s | 13,8 | 10 | 10,4 | 6,88 |
Texture bandwidth, number of pixels of pipelines x frequency, |
36,8 | 32 | 15,6 | 10,32 |
| RAMDAC, MHz | 400 | 400 | 400 | 400 |
cooler.
Speaking about the processor, one cannot forget one more detail, without which a modern processor cannot work. We are talking about a cooler - a special cooling fan that is installed on top of the processor chip.
Motherboard .
The motherboard is a very complex system, each part of which depends on the speed and stability of the computer.
The logical groups of devices that make up the system board:
· A set of connectors and ports for connecting individual devices.
· A bus is an information highway linking them together.
It is through the bus that signals are transmitted between all types of computer "stuffing" and it is through the bus that information is delivered to the processor.
The basic "chipset" chipset, with which motherboard and exercises control over everything that happens inside the system unit. It depends on the chipset what type of processors and memory the motherboard will support.
Small BIOS chip.
· Built-in (or integrated) options.
RAM
The difference between random access memory and permanent, disk memory is that information is stored in it not permanently, but temporarily. Moreover, the charge in the RAM cells disappears without a trace in milliseconds even when the computer is turned on - and in order for the necessary data not to disappear ahead of time, the computer is forced to constantly update them. Access to RAM is much faster than to disk: the access time of the most modern hard drive(hard drive) is 8 - 10 milliseconds (ms). And modern RAM has an access time of 3 - 7 nanoseconds (ns). RAM is used in a variety of PC devices - from a video card to a laser printer.
Video card
Creating a three-dimensional, realistic image is not an easy task. In fact, the video card has to perform several complex operations. A few years ago, shaders were built into the boards, which would make 3D models more lively and believable. For example, thanks to pixel shaders, the video card can control lighting effects (fog, flames, etc.). The task of any video card is to show any game object from any point of view: from above, from the side, and sometimes from below.
Most video cards today are equipped with a special TV - output (analogue SVGA or digital HDMI) - in order to be able to output a picture from a computer to a TV screen using a special cable.
The main "think tank" of any video card is a specialized graphics chip, a microcircuit that combines the parts responsible for working with conventional, two-dimensional, and three-dimensional game graphics. Modern boards based on the GeForce 9800 chip can produce about 20 billion pixels per second.
Sound card
The first ten years of its existence Personal Computer did without sound - not counting the vile squeaking of the built-in speaker. Then came a company that proved that their computer could sound like an average music center. Until the end of the 90s, sound cards improved, improved the sound quality. And along the way, new opportunities have grown. When the fashion for MIDI finally came to naught, manufacturers switched to supporting multi-channel, built-in effects.
Today on most motherboards an HDI (HighDefinitionAudio) sound subsystem with support for eight-channel sound and hardware processing of surround effects is already installed.
HDD
The first computing devices could not store information on some external or internal media. Information was stored on paper strips with punched holes - punched tape. In the late 1940s, perforated paper was replaced by magnetic recording. The information carrier here is a layer of magnetic material, the thickness of which is fractions of a micron. It is this film, placed on a glass or metal base, that stores all those gigabytes of information with which a personal computer is packed.
Any "hard drive" consists of three main blocks.
· First block and there is, the information storage itself is one of several glass (or metal) disks coated on both sides with magnetic material, on which data is recorded.
· Second block- the mechanics of the hard drive, responsible for the rotation of this array of "pancakes", and more precisely the positioning of the system of reading heads. Each working surface of the hard disk corresponds to one reading head. As one of the most important technological parameters of any disk, it is the number of reading heads that is indicated, and not the number of working surfaces that coincides with it.
· Third block includes electronic stuffing - microcircuits responsible for data processing, correction possible errors and control of the mechanical part, as well as cache memory chips.
Optical drives
The personal computer contains optical drives.
Initially, floppy disks played the role of information carriers. The first generation of optical media were compact discs (CDs), containing up to 650 MB of information. In 1995, even more capacious media appeared - DVD (DigitalVersatileDisc), their capacity is 4.7 GB. In 2005, another technological leap took place, which gave birth to two new media at once: Blu-Ray and HD-DVD.
The carrier of information on all types of optical drives is a relief polycarbonate substrate, on which a thin layer of a light-reflecting substance is deposited. When reading a disc, the “reading” laser beam is reflected from the recorded and clean areas in different ways - in one case it is absorbed, in the other it returns to the reading laser head in a reflected form.
Optical drives are available in both internal and external versions. Internal drives can be designed to connect to the standard IDE interface, or to the new SerialATA interface. External models usually work with high-speed USB2.0 or FireWire (IEEE 1394) connectors.
1.2 External devices of a personal computer
In addition to devices that are hidden in system block(components), a decent computer should be equipped with additional, external devices. Of course, the system unit performs the lion's share of the processing and storage of information. But the information must appear from somewhere, and the result of its processing is sent where it should be. For this, in particular, external devices are responsible - they, depending on the type of work performed, are usually divided into input and output devices.
Monitor
At one time, the computer successfully managed without a monitor. Engineers had to count holes on a punched card, decipher the flickering of light bulbs. The first monitors appeared in the mid-seventies. Since that time the monitors have gone long haul changed in appearance. The only thing that has remained unchanged is the high price.
types of monitors. Until the beginning of this century, advanced televisions acted as monitors - boxes based on a cathode ray tube (CRT)
The advantages of CRT are well known: rather low price, excellent color rendering. This is where the advantages end and the disadvantages begin: bulkiness, huge electricity consumption, and most importantly, a harmful effect on the eyes.
The LCD has many advantages over the traditional CRT. They are compact and lightweight, their thickness is only a few centimeters, they are safe in medical and environmental terms, and consume several times less energy. And most importantly, they have a flat screen, better than the traditional convex. Another advantage of LCD monitors is the digital method of transmitting information.
Keyboard
The keyboard is both an input device and a control device. All keys available on the computer are divided into 4 groups:
Typewriter keys or alphanumeric block;
service keys that control keyboard input, including in the form of changing the meaning of pressing other keys;
· function keys(F1 - F12);
· Optional dual-mode keyboard. It is located on the right side of the keyboard and can be used both for entering characters (numbers) and for control. The operating mode is switched using the Num Lock key.
Typewriter keys for entering information (characters). Pressing each of these keys sends a command to the computer to display a letter or number on the screen. The meaning of these keys is constant and does not change - regardless of the programs running on the computer.
Service keys.
· Enter (input) - pressing this key allows you to execute any of the selected commands.
· Esc – terminate the operation.
· CapsLock – turn on the capital letter mode.
· Shift - when working in text mode, pressing this key simultaneously with an alphabetic key will display a large, uppercase letter.
· PageUp – “scrolling” the image up.
· PageDown - "scrolling" the image down.
· Backspace - delete the last character.
· Del – key for deleting selected text, file, etc.
Ins is the opposite of Delete command. Insert and create key.
· Home– move to the beginning/left edge of the line/screen
End - go to the end/right edge of the line/screen
· Tab - insert tabulation (indent to a predetermined position).
PrintScreen - this button allows you to take a "picture" from the computer screen, placing it on the "clipboard"
Mouse
In fact, with its help, all available operations are performed - except for entering text.
According to the type of connection to a computer, mice are divided into wired and infrared. In the latter case, not a wire is connected to the port on the system unit, but an infrared signal receiver. Another important indicator of the mouse is ergonomics.
1.3 Classification and characteristics of computers
Among the many modern computers, the main classes can be distinguished:
supercomputer;
· large computing complexes (BVK);
· mini-computer;
personal computers.
Supercomputers are designed to solve extremely complex tasks in military affairs, economics, cosmonautics, meteorology, etc. These are very complex and expensive machines. The most powerful computers of this class - the ASCI family - belong to the US Department of Energy. Their productivity exceeds 1 trillion. floating point operations per second. The United States is trying to use them to implement a project for the transition from natural nuclear tests to computer simulation. There are about 500 machines of this level in the world. The best PCs are approximately 100,000 times weaker than supercomputers in terms of performance.
Large computer systems (BVK) called "Mainframes" are still being produced, but modern technologies have made it possible to drastically reduce their dimensions: weight up to 100 kg; occupied area up to
. Their scope is the solution of especially important tasks in the military, financial and other fields - where exceptional reliability is required. They use all known means of improving the performance and reliability of computing systems.Mini-computer. Previously, they were used in small organizations for relatively simple tasks. Modern mini-computers, thanks to the achievements of microelectronics, are equal in size to PCs, having a huge superiority over the latter in performance and reliability. They are used, for example, in the banking sector, as servers (central computers) of highly reliable local computer networks with up to 300 workstations.
Personal computers (PC). They, having great potential, ousted BVK and mini-computers from many areas of activity. Indeed, their possibilities are great. By design, PCs are divided into several types:
desktop;
knee (Laptop) (3 - 6 kg);
notepads (NoteBook) (2 - 3.5 kg);
Super notebook (SubNoteBook) (0.9 - 2 kg);
Pocket (Palmtop) (0.5 - 1.2 kg);
electronic notebooks.
Approximate parameters of a modern portable computer: this is a complete PC, weight - 0.9 kg, overall dimensions
cm, clock frequency - up to 2 GHz, RAM - up to 1 GB, hard drive capacity - up to 40 GB.2. ARCHITECTURE OF A PERSONAL COMPUTER
PC architecture is a combination of hardware and software tools PC, as well as their interaction system, which ensures the functioning of the PC.
The term "architecture" is used quite often in the popular literature on computing, but the definition of this concept and its content may vary. The description of the internal structure of a PC is not an end in itself: from the point of view of architecture, only those connections and principles that are the most general, inherent in many specific implementations of computers, are of interest.
2.1 Principles of building a PC
It is that common thing that is in the structure of a PC that is referred to as the concept of architecture. It is important to note that such a generality is ultimately served by a completely understandable desire: all machines of the same family, regardless of their specific device and the manufacturer must be able to carry out the same program. It follows that from the point of view of architecture, not all information about the construction of a PC is important, but only those that can somehow be used when programming and working with a PC.
The following is a list of the most general principles for building a PC that relate to architecture:
PC memory structure;
ways to access memory and external devices;
the ability to change the configuration of the computer;
command system;
· data formats;
interface organization.
Summarizing all of the above, we obtain the following definition of architecture: “Architecture is the most general principles for building computers that implement software control of the operation and interaction of its main functional units”
2.2 Fundamentals of the doctrine and structure of the first generations of computers
The foundations of the theory of computer architecture were laid by the outstanding American mathematician John von Neumann. In the process of work, during numerous discussions with his colleagues G. Goldstein and A. Berks, von Neumann expressed the idea of a fundamentally new computer. Von Neumann not only put forward the fundamental principles of the logical structure of the computer, but also suggested its structure, which was reproduced during the first two generations of computers. The main units according to Neumann are the control unit (CU) and the arithmetic logic unit (ALU), memory, external memory, input and output devices. The scheme of the device of such a computer is shown in Figure 1.
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Rice. 1. The architecture of a computer built on the principles of von Neumann.
The foundations of the architecture of computing devices developed by von Neumann turned out to be so fundamental that they received the name “von Neumann architecture” in the literature. The vast majority of computers today are von Neumann machines. A significant departure from the von Neumann architecture will occur as a result of the development of the idea of fifth-generation machines, in which information processing is based not on calculations, but on logical conclusions.
3. DEVICE OF THE CENTRAL PROCESSOR
There is more than one processor in a computer: a video card, a sound card, and many external devices (for example, a printer) have their own processor. And often in terms of performance, these microcircuits can compete with the main, Central Processor. But unlike him, one is responsible for sound processing, the other for creating a three-dimensional image. The main and main difference of the central processor is its versatility. The CPU can take over any work, while the processor of the video card cannot decode the music file.
3.1 CPU functions
The central processor is a device that provides data processing according to a given program. The central processor performs the following main types of operations: command execution, interruption, reset, state registration (recording information about the state of the computer system as a whole or its individual components in certain areas of the main memory). The processor selects the program and the data processed according to it from the main (random) memory.
The central processor performs the main work of converting data in the computer system and, in addition, performs automated control functions in it in accordance with the algorithms of the operating system control program. In particular, the CPU interacts with the I/O channels, initiating I/O operations and receiving information about the results of their execution, as well as the state of the I/O system.
The processor includes, in most cases, one or more operational (or arithmetic-logical units), a control device, local memory, monitoring and diagnostic tools.
The Arithmetic Logic Unit (ALU) performs data conversion operations. It includes one or more adders and registers for storing intermediate data and transformation results.
The arithmetic logic unit can be expanded with specialized operating units: with a motor, a fast multiplier, a decimal adder, a converter, etc.
3.2 Operating controls
The control device (CU) is an automatic machine that controls the processes of transferring and processing information in the processor. This device receives commands and generates a sequence of control signals, checks, etc. It is included in the work of functional units by issuing synchronizing and control signals.
The processor may contain local memory for various functional purposes: working registers, RON, pointer registers, control registers, service word registers, etc. Service memory can be used for buffering data and commands, storing address translation tables, security keys.
The processor may include a set of special system tools: time service (daily clock, timer, etc.), interprocessor communication tools, system control panel, etc. Monitoring and diagnostic tools allow you to detect and eliminate faults without loss of processor performance.
From a logical point of view, the processor consists of many cells that process information - registers. Such a register can store from 1 to 8 bytes of information.
On any processor chip are:
Processor core, the main computing device. It is here that the processing of all incoming data to the processor takes place.
· Coprocessor - an additional block for the most complex mathematical calculations, including operations with "floating point". It is actively used, in particular, when working with graphic and multimedia programs.
· Cache - memory. Buffer memory is a kind of storage for data. Modern processors use two types of cache - memory: the first level - a small (several tens of kilobytes) ultra-fast memory and the second level - a little slower, but more - from 128 KB to 2 MB.
All these devices are placed on a chip with an area of no more than 4 - 6
. One processor cannot cope with information processing: for this it needs to handle many others. computer devices: hard drive, RAM, etc. To do this, there is a special high-speed highway in the computer, through which data is transmitted to the processor and vice versa - it is called the "bus".CONCLUSION
Experts from ufology in all seriousness prove that the computer era should be counted from 1949, when the famous “flying saucer” crashed to Earth. Allegedly, when gutting its remains, those parts were found that later turned into the first microprocessors. At first, scientists had to invent transistors, then integrated circuits, and a quarter of a century later, the microprocessor.
In 1970, Dr. Hoff and his management team designed the first microprocessor. Its appearance changed the entire microelectronics market, and it was they who contributed to the emergence of the very computers with which we work today.
Today we are on the verge of the emergence of computers of a new, fifth generation, based on nanotechnologies: in them, the role of information custodians and processors will no longer be assumed by silicon processors, but by special organic molecules! AT modern memory based on silicon chips, more than 20 atoms are used to store a single bit!
Fifth generation machine models are focused on streaming architecture, on the implementation of an intelligent human-machine interface that provides not only system solution tasks, but also the ability of the machine to think logically, to self-learn, associative processing of information and drawing logical conclusions.
A modern engineer, economist, lawyer, doctor must have knowledge in the field of computer science and practical skills in using computers, communication systems and information transmission, be able to assess the accuracy and completeness of information that affects managerial decision-making.
TASK #2
Conduct an annual calculation of the scope of work and their cost of DRSU No. 1, consisting of three departments using MSExcel functions. Build pie chart the scope of work and its cost for the year of DRSU No. 1 as a whole, depending on the month.
| Winter | 1,5 |
| Spring | 1,25 |
| Summer | 1 |
| Autumn | 1,25 |
| Scope and cost of work in Department No. 1 | ||||||||
| Month | Asphalt removal | Web preparation | Asphalt paving | For department 1 | ||||
| Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | |
| January | 808 | 545400,0 | 789 | 272205,0 | 779 | 736155,0 | 2376 | 1553760,0 |
| February | 865 | 583875,0 | 827 | 285315,0 | 808 | 763560,0 | 2500 | 1632750,0 |
| March | 1064 | 598500,0 | 931 | 267662,5 | 893 | 703237,5 | 2888 | 1569400,0 |
| April | 1188 | 668250,0 | 1178 | 338675,0 | 1169 | 920587,5 | 3535 | 1927512,5 |
| May | 1302 | 732375,0 | 1292 | 371450,0 | 1283 | 1010362,5 | 3877 | 2114187,5 |
| June | 1568 | 705600,0 | 1558 | 358340,0 | 1549 | 975870,0 | 4675 | 2039810,0 |
| July | 1663 | 748350,0 | 1672 | 384560,0 | 1691 | 1065330,0 | 5026 | 2198240,0 |
| August | 1587 | 714150,0 | 1625 | 373750,0 | 1615 | 1017450,0 | 4827 | 2105350,0 |
| September | 1691 | 951187,5 | 1663 | 478112,5 | 1672 | 1316700,0 | 5026 | 2746000,0 |
| October | 1292 | 726750,0 | 1283 | 368862,5 | 1273 | 1002487,5 | 3848 | 2098100,0 |
| November | 1188 | 668250,0 | 1131 | 325162,5 | 1140 | 897750,0 | 3459 | 1891162,5 |
| December | 884 | 596700,0 | 874 | 301530,0 | 893 | 843885,0 | 2651 | 1742115,0 |
| Total | 15100 | 8239387,5 | 14823 | 4125625,0 | 14765 | 11253375,0 | 44688 | 23618387,5 |
| Wed value | 1258,3 | 686615,6 | 1235,3 | 343802,1 | 1230,4 | 937781,3 | 3724,0 | 1968199,0 |
| Max. Zn. | 1691,0 | 951187,5 | 1672,0 | 478112,5 | 1691,0 | 1316700,0 | 5054,0 | 2746000,0 |
| Min. Zn. | 808,0 | 545400,0 | 789,0 | 267662,5 | 779,0 | 703237,5 | 2376,0 | 1516300,0 |
| Coefficients of the seasons (K vg) | |
| Winter | 1,5 |
| Spring | 1,25 |
| Summer | 1 |
| Autumn | 1,25 |
| Scope and cost of work in Department No. 2 | ||||||||
| Month | Asphalt removal | Web preparation | Asphalt paving | For branch 2 | ||||
| Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | |
| January | 929,2 | 627210,0 | 907,35 | 313035,8 | 895,85 | 846578,3 | 2732,4 | 1786824,0 |
| February | 951,5 | 273556,3 | 909,7 | 313846,5 | 888,8 | 839916,0 | 2750 | 1427318,8 |
| March | 1276,8 | 718200,0 | 1117,2 | 321195,0 | 1071,6 | 843885,0 | 3465,6 | 1883280,0 |
| April | 1485,0 | 835312,5 | 1472,5 | 423343,8 | 1461,3 | 1150734,4 | 4418,75 | 2409390,6 |
| May | 1692,6 | 952087,5 | 1679,6 | 482885,0 | 1667,9 | 1313471,3 | 5040,1 | 2748443,8 |
| June | 2195,2 | 987840,0 | 2181,2 | 501676,0 | 2168,6 | 1366218,0 | 6545 | 2855734,0 |
| July | 2328,2 | 1047690,0 | 2340,8 | 538384,0 | 2367,4 | 1491462,0 | 7036,4 | 3077536,0 |
| August | 2142,5 | 964102,5 | 2193,8 | 504562,5 | 2180,3 | 1373557,5 | 6516,45 | 2842222,5 |
| September | 2367,4 | 1331662,5 | 2328,2 | 669357,5 | 2340,8 | 1843380,0 | 7036,4 | 3844400,0 |
| October | 1679,6 | 944775,0 | 1667,9 | 479521,3 | 1654,9 | 1303233,8 | 5002,4 | 2727530,0 |
| November | 1425,6 | 801900,0 | 1357,2 | 390195,0 | 1368,0 | 1077300,0 | 4150,8 | 2269395,0 |
| December | 1016,6 | 686205,0 | 1005,1 | 346759,5 | 1027,0 | 970467,8 | 3048,65 | 2003432,3 |
| Total | 19490,2 | 10170541,3 | 19160,5 | 5284761,8 | 19092,3 | 14420203,9 | 57742,95 | 29875506,9 |
| Wed value | 1624,2 | 847545,1 | 1596,7 | 440396,8 | 1591,0 | 1201683,7 | 4811,9 | 2489625,6 |
| Max. Zn. | 2367,4 | 1331662,5 | 2340,8 | 669357,5 | 2367,4 | 1843380,0 | 7075,6 | 3844400,0 |
| Min. Zn. | 929,2 | 273556,3 | 907,4 | 313035,8 | 888,8 | 839916,0 | 2725,4 | 1426508,0 |
| Scope and cost of work in Department No. 3 | ||||||||
| Month | Asphalt removal | Web preparation | Asphalt paving | For branch 3 | ||||
| Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | |
| January | 1022,1 | 689931,0 | 998,085 | 344339,3 | 985,435 | 931236,1 | 3175,6 | 1965506,4 |
| February | 1237,0 | 834941,3 | 1182,61 | 408000,5 | 1155,44 | 1091890,8 | 3575,0 | 2334832,5 |
| March | 1659,8 | 933660,0 | 1452,36 | 417553,5 | 1393,08 | 1097050,5 | 4505,3 | 2448264,0 |
| April | 2004,8 | 1127671,9 | 1987,875 | 571514,1 | 1972,688 | 1553491,4 | 5965,3 | 3252677,3 |
| May | 2369,6 | 1332922,5 | 2351,44 | 676039,0 | 2335,06 | 1838859,8 | 7056,1 | 3847821,3 |
| June | 3073,3 | 1382976,0 | 3053,68 | 702346,4 | 3036,04 | 1912705,2 | 9163,0 | 3998027,6 |
| July | 3492,3 | 1571535,0 | 3511,2 | 807576,0 | 3551,1 | 2237193,0 | 10554,6 | 4616304,0 |
| August | 3106,6 | 1397948,6 | 3180,938 | 731615,6 | 3161,363 | 1991658,4 | 9448,9 | 4121222,6 |
| September | 3314,4 | 1864327,5 | 3259,48 | 937100,5 | 3277,12 | 2580732,0 | 9851,0 | 5382160,0 |
| October | 2519,4 | 1417162,5 | 2501,85 | 719281,9 | 2482,35 | 1954850,6 | 7503,6 | 4091295,0 |
| November | 1853,3 | 1042470,0 | 1764,36 | 507253,5 | 1778,4 | 1400490,0 | 5396,0 | 2950213,5 |
| December | 1270,8 | 857756,3 | 1256,375 | 433449,4 | 1283,688 | 1213084,7 | 3810,8 | 2504290,3 |
| Total | 26923,2 | 14453302,5 | 26500,25 | 7256069,6 | 26411,76 | 19803242,4 | 80005,24 | 41512614,5 |
| Wed value | 2243,6 | 1204441,9 | 2208,4 | 604672,5 | 2201,0 | 1650270,2 | 6652,9 | 3459384,5 |
| Max. Zn. | 3492,3 | 1864327,5 | 3511,2 | 937100,5 | 3551,1 | 2580732,0 | 10554,6 | 5382160,0 |
| Min. Zn. | 1022,1 | 689931,0 | 998,1 | 344339,3 | 985,4 | 931236,1 | 3005,6 | 1965506,4 |
Scope and cost of work under DRSU No. 1 |
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| Month | Asphalt removal | Web preparation | Asphalt paving | For DRSU No. 1 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | Volume | We are standing. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| January | 2759,3 | 1862541,0 | 2694,435 | 929580,1 | 2660,285 | 2513969,3 | 8114,0 | 5306090,4 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| February | 3053,5 | 1692372,5 | 2919,31 | 1007162,0 | 2852,24 | 2695366,8 | 8825,0 | 5394901,3 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| March | 4000,6 | 2250360,0 | 3500,56 | 1006411,0 | 3357,68 | 2644173,0 | 10858,9 | 5900944,0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| April | 4677,8 | 2631234,4 | 4638,375 | 1333532,8 | 4602,938 | 3624813,3 | 13919,1 | 7589580,5 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| May | 5364,2 | 3017385,0 | 5323,04 | 1530374,0 | 5285,96 | 4162693,5 | 15973,2 | 8710452,5 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| June | 6836,5 | 3076416,0 | 6792,88 | 1562362,4 | 6753,64 | 4254793,2 | 20383,0 | 8893571,6 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| July | 7483,5 | 3367575,0 | 7524 | 1730520,0 | 7609,5 | 4793985,0 | 22617,0 | 9892080,0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| August | 6836,0 | 3076201,1 | 6999,688 | 1609928,1 | 6956,613 | 4382665,9 | 20792,3 | 9068795,1 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| September | 7372,8 | 4147177,5 | 7250,68 | 2084570,5 | 7289,92 | 5740812,0 | 21913,4 | 11972560,0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| October | 5491,0 | 3088687,5 | 5452,75 | 1567665,6 | 5410,25 | 4260571,9 | 16354,0 | 8916925,0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| November | 4466,9 | 2512620,0 | 4252,56 | 1222611,0 | 4286,4 | 3375540,0 | 13005,8 | 7110771,0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| December | 3171,4 | 2140661,3 | 3135,475 | 1081738,9 | 3203,638 | 3027437,4 | 9510,5 | 6249837,6 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Total | 61513,4 | 32863231,3 | 60483,75 | 16666456,4 | 60269,06 | 45476821,3 | 182266,2 | 95006508,9 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Wed value | 5126,1 | 2738602,6 | 5040,3 | 1388871,4 | 5022,4 | 3789735,1 | 15188,8 | 7917209,1 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Max. Zn. | 7483,5 | 4147177,5 | 7524,0 | 2084570,5 | 7609,5 | 5740812,0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Table 1 "Routes" | |||||
| The code | Driver | Route | the date | Time | Bus brand |
| 1 | Vetrov N.V. | Krasnodar-Sochi | 06.12.2004 | 6:40:00 | "Ikarus" |
| 2 | Sitnichenko A.I. | Krasnodar-Gelendzhik | 06.12.2004 | 7:00:00 | "LIAZ" |
| 3 | Chusov V.A. | Krasnodar-Anapa | 06.12.2004 | 7:15:00 | "Higer" |
| 4 | Vinichenko E.R. | Krasnodar-Kropotkin | 01.10.2004 | 7:20:00 | "Opel" |
| 5 | Marusov A.G. | Krasnodar-Rostov | 09.12.2004 | 7:25:00 | "Setra" |
| 6 | Kantaurov I.O. | Krasnodar-Armavir | 08.12.2004 | 7:30:00 | "Neoplan" |
| Krasnodar-Anapa | |||||
| 01.10.2004 | 7:20:00 | Krasnodar-Kropotkin | |||
| 09.12.2004 | 7:25:00 | Krasnodar-Rostov | |||
| 08.12.2004 | 7:30:00 | Krasnodar-Armavir | |||
| 12.10.2004 | 20:35:00 | Temryuk-Tuapse | |||
Report 1 Date of routes
CodeDateBus brandDriverRouteTime
12/106/20 "Ikarus" Vetrov N.V. Krasnodar-Sochi6:40:00
206.12.20 "LIAZ" Sitnichenko A.I. Krasnodar-Gelendzhik7:00:00
306.12.20 Haiger Chusov V.A. Krasnodar-Anapa7:15:00
401.10.20 "Opel" Vinichenko E.R. Krasnodar-Kropotkin7:20:00
509.12.20 "Setra" Marusov A.G. Krasnodar-Rostov7:25:00
608.12.20 "Neoplan" Kantaurov I.O. Krasnodar-Armavir7:30:00
712.10.20 Mercedes Gurov G.A.Temryuk-Tuapse20:35:0
Report 2 Seats on buses
CodeBus brandNumber of seatsFactory
1"Ikarus"65Hungary
2"LIAZ"40Russia
3"Higer"42China
4"Opel"45Germany
5"Setra"41Germany
6"Neoplan"44Germany
7"Mercedes"40Minsk
LIST OF USED LITERATURE
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2. S.E. Zelinsky "PC. Devices, peripherals, components. – 2005
3. S.V. Glushakov, A.S. Suryadny "Personal Computer". – 2002
4. A course of lectures on general informatics / Atroshchenko V.A. and others - Krasnodar: 2006.
5. Computer science. Workshop. Textbook / Atroshchenko V. A and others - Krasnodar: 2005
6. Informatics: Basic course / S.V. Simonovich and others - St. Petersburg: Peter, 2001.
7. Informatics: Textbook / Ed. Prof. N.V. Makarova. - M.: Finance and statistics, 2003.
8. Informatics: Workshop on computer technology / Ed. Prof.
9. Figurnov V.E. IBM PC for the user. Ed. 7th, revised. and additional - M .: INFRA-M, 2000
10. Epaneshnikov V. Programming in Turbo Pascal 7.0. M.: Radio and communication. 2001
11. Leontiev V.P. The latest encyclopedia of a personal computer 2008. - M .: OLMA Media Group, 2008
12. Ostreikovskiy V.A. Informatics: Proc. for universities. - M .: Higher School, 2000