Presentation on computer science on the topic "Composite parts of a computer block". Computer device

The word computer is known to any baby!

Here it is computer: monitor, mouse, keyboard, and system unit:

The main parts of the computer - the processor and memory - are contained inside system Block. And the monitor, keyboard and mouse are input and output devices.

From keyboard and mouse computer introduces Text and teams. On the computer monitor displays Text and drawings. That is why these devices call input and output devices.

	This is a monitor. It looks like a TV. A computer displays On its screen, texts and pictures. The monitor is an output device. The letter "K" in the figure is conditionally indicated by the computer, and the arrow shows that the information output From the computer to the monitor.
	This is a keyboard. It serves to set ( input) Text: From the keyboard it is possible enter Commands, for example, arrod keys to control the hero on the screen: The keyboard is an input device. Arrow in the picture on the left shows that the information from the keyboard introduced to computer.
	This is a computer mouse. Mouse Movement Repeats the arrow on the monitor screen. This arrow is the cursor. The mouse has buttons that you can click - Set ( enter) Teams. Mouse is an input device.
	This is a system unit. There are: processor ("brain" of a computer); information storage devices (Computer Memory).
	If you open a system unit, you can see the processor and computer memory.
	Figure conventionally shown that the information from the keyboard and mouse introduced to the computer, and from the computer - output on the monitor. The keyboard and mouse are computer input devices. Monitor - output device.
	We are talking about entering information into a computer and withdrawing it from the computer. The question arises: where exactly the information is introduced and where does it come from? What device does the computer store in the computer? Of course, that's computer memory! In memory of the computer, information comes from the keyboard and mouse. It is displayed on the monitor.

So, what is our usual personal computer (PC), which we use at home or at work.

Consider its hardware ("Iron"):

• system block (the large box that is on your table or under the table, on the side of it, etc.). It contains all basic computer nodes.
• peripherals (Such as a monitor, keyboard, mouse, modem, scanner, etc.).

The system unit in the computer is "main". If you carefully unscrew the screws from its back wall, remove the sidebar and look inside, then only with the form of its device will seem complex. Now I will briefly describe his device, and then characterize the main elements in the most understandable language.

The system block contains the following elements (not necessarily all at once):

- Power Supply

- Hard magnetic disk drive (HDD)

- Drive on flexible magnetic disk (FDD)

- Drive on a CD or DVD (CD / DVD ROM)

- Connectors for additional devices (ports) on the rear (sometimes on the front) panel, etc.

- The motherboard (it is more often called the maternal), which, in turn, contains:

• microprocessor;
• mathematical coprocessor;
• clock pulse generator;
• memory chips (RAM, ROM, CASH memory, CMOS memory)
• controllers (adapters) of devices: keyboards, disks, etc.
• sound, video and network card;
• timer and others.

All of them are connected to the motherboard using connectors (slots). Its elements highlighted in bold, we will consider below.

And now in order about the system unit:

one . With the power supply, everything is clear: it feeds the energy of the computer. I will only say that, the higher its power indicator, the cooler.

2. Hard magnetic disk drive (HDD - hard Disk. Drive) in commoner called Winchester.

This nickname arose from the jargon name of the first model. hard disk The capacity of 16 KB (IBM, 1973), which had 30 tracks of 30 sectors, which accidentally coincided with the "30/30" hunting rifle of the famous Hunting rifle. The container of this drive is usually measured in gigabytes: from 20 GB (on old computers) to several terrabytes (1TB \u003d 1024 GB). The most common capacity of the hard drive is 250-500 GB. The speed of operations depends on the speed of rotation (5400-10000 rpm). Depending on the type of hard drive with motherboard distinguish ATA and IDE.

3. Drive on a flexible magnetic disk (FDD - FLOPPY DISK Drive) - nothing but floppy disk drive. Their standard capacity is 1.44 MB with a diameter of 3.5 "(89 mm). Magnetic materials with special properties are used as a storage medium with special properties that allow you to record two magnetic states, each of which is put into line with binary numbers: 0 and one.

4 . Drives on optical disks (CD-ROM) There are different diameters (3.5 "and 5.25") and tanks. The most common ones are a capacity of 700 MB. It happens that CDs can be used to record only 1 time (then they are called R), and it is more profitable to use repeatedly rewritable RW discs.

DVD was initially decrypted as Digital Video Disk. Despite the name, you can write anything on DVDs anything, from music to data. Therefore, in recent times, the other decoding of this name is the Digital Versatile Disk, in the free translation of the "digital universal disk". The main difference between DVDs from CDs is the volume of information that can be recorded on such a carrier. The DVD can be recorded from 4.7 to 13, and even up to 17 GB. This is achieved in several ways. First, a laser with a smaller wavelength is used to read DVDs than to read CDs, which made it possible to significantly increase the recording density. Secondly, the standard provides so-called two-layer discs, in which the data on one side are recorded in two layers, while one layer of translucent, and the second layer is read "through" the first. This made it possible to record data on both sides of DVDs, and thus double their capacity, which is sometimes done.

five . Other additional devices can be connected to the personal computer ( mouse, printer, scanner andother). Connection is performed through ports - special connectors on the rear panel.

Ports are parallel (LPT), serial (COM) and universal serial (USB). According to the serial port, the information is transmitted on the paired (more slowly) at a small number of wires. Mouse and modem are connected to the serial port. By parallel port, the information is transmitted simultaneously by a large number of wires corresponding to the number of discharges. The parallel port is connected to the printer and remote hard drive. The USB port is used to connect a wide spectrum of peripheral devices - from the mouse to the printer. It is also possible to exchange data between computers.

6. The main devices of the computer (processor, RAM, etc.) are placed on motherboard.

Microprocessor (easier - processor) - a central PC unit designed to manage the work of all machine blocks and to perform arithmetic and logical operations on information.

Its main characteristics are a bit (than it is higher, the higher the performance of the computer) and the clock frequency (largely determines the speed of the computer). The clock frequency indicates how many elementary operations (clocks) processor performs in one second.
Respect in the processor market Intel Pentium. and its economy version of Celeron, and also appreciate their competitors - AMD Athlon. With economy version of Duron. Intel processors Characterized by high reliability in work, low heat generation and compatibility with all software and hardware. And AMD show a greater speed of working with graphics and games, but less reliable.

Computer memory is internal and external. To devices external memory There are already considered HDD, FDD, CD-ROM, DVD-ROM. TO internal memory Refers constant memory (ROM, ROM English), operational memory (RAM, RAM English), cache.

The ROM is intended for storing constant software and reference information (BIOS - Basic Input-Output System - basic I / O system).

RAM has high speed and is used by the processor for short-term storage of information during computer operation.

When the power source is turned off, the information in the RAM is not saved. For the normal functioning of the computer today, it is advisable to have from 1 GB to 3 GB of RAM.

Cache memory is an operational ultra-speed intermediate memory.

CMOS memory - CMOS RAM (Compledenary Metall-Oxide Semiconductor RAM). It stores the computer configuration parameters that are checked each time the system is turned on. To change the computer configuration settings in the BIOS contains a computer configuration configuration program - SETUP.

Sound, Video and Network Cards It can be both built-in motherboards and external. External boards can always be replaced, whereas if the built-in video card comes out, you will have to change the entire motherboard. I trust from video cards ATI Radeon. and NVIDIA. The higher the memory of the video card, the better.

Peripherals

Computer consists of 6 key groups:

• Alphanumeric;
• Managers (Enter, Backspace, Ctrl, Alt, Shift, Tab, ESC, Caps Lock., Num Lock, Scroll Lock, Pause, Print Screen);
• Functional (F1-F12);
• Numeric keypad;
• Cursor control (-\u003e,<-, Page Up, Page Down, Home, End, Delete, Insert);
• Light indicators of features (CAPS LOCK, NUM LOCK, SCROLL LOCK).

Mouse (mechanical, optical). Most programs use two of the three mouse keys. The left key is the main one, it is controlled by a computer. She plays the Enter key role. The functions of the right key depend on the program. In the middle there is a scroll wheel to which you quickly get used to.

Modem - network adapter. It can be both external and inner.

The scanner automatically reads with paper media and enters in PC any printed texts and images.

The microphone is used to enter sound to the computer.

(Display) Designed to display information on the screen. Most often in modern PCs are used by SVGA monitors with resolution (by the number of points placed horizontally and vertically on the monitor screen) 800 * 600, 1024 * 768, 1280 * 1024, 1600 * 1200 during transmission to 16.8 million colors.

The size of the monitor screen is from 15 to 22 inches diagonally, but most often - 17 inches (35.5 cm). The size of the point (grain) is from 0.32 mm to 0.21 mm. What he is less, the better.

PCs that are equipped with television monitors (CRT) are not so popular. Of these, preference should be given to low radiation monitors (Low Radiation). Liquid crystal displays (LCD) are safer, and most computers have exactly such a monitor.

Designed for printing text and graphic images. Printers are matrix, inkjet and laser. In matrix printers, the image is formed from the shock points. Inkjet printers in the print head instead of needles have thin tubes - nozzles, through which the smallest droplets of ink are thrown on paper. Inkjet printers are performed and color printing with basic colors. Dignity - high quality Print, disadvantage - the danger of drying ink, the high cost of consumables.

In laser printers, an electrographic method of image formation is used. The laser serves to create an ultra-thin light beam, drawing on the surface of the pre-charged photosensitive drum contours of an invisible point electronic image. After the e-image manifestation of the dye powder (toner), sticking to the discharged sections, printing is performed - the transfer of toner from the drum on paper and fasten the image on the toner warming paper before melting it. Laser printers provide the highest quality printing with high speed. Color laser printers are widely used.

Sound columns Displays sound. The sound quality depends - again - from the power of the speakers and the material from which the housings are made (preferably a tree) and its volume. An important role is played by the presence of a phase inverter (hole on the front panel) and the number of bands of reproducible frequencies (high, medium and low speakers on each column).

USB drives on flash memory, in my opinion, have become the most universal means of transferring information. This is a miniature device size and weight less lighter. It has high mechanical strength, it is not afraid of electromagnetic emissions, heat and cold, dust and dirt.

The most sensitive part of the drive is a connector covered with a cap. The volume of these devices ranges from 256 MB to 32 GB, which allows you to choose the drive of the desired container, consistent with the needs. Thanks to the interface, the USB drive can be connected to any modern computer. It works with Windows 98SE / ME / 2000 / XP / VISTA / 7, Mac OS 8.6 ~ 10.1, Linux 2.4 operating systems. In Windows, you do not even need to install any drivers: connected to USB port - and work.

Need to enter a dynamic image to a computer and sound (to communicate and the possibility of creating teleconferences).

Uninterruptible power system Need for an emergency power outage of electricity.

Fuff, well, in my opinion, and everything is the main thing that I wanted to tell you about the hardware of the computer, the so-called Hardware.

The article "Computer Device" was written for quite a long time. Therefore, if you found a mistake or discovered some inaccuracy, please write about it using the comment form. We will be very grateful!

Equipment:

• Schemes of the device (UGNOVIC), motherboard, processor, monitors, types of memory, memory);
• Computer elements

Lesson 1. Internal computer architecture (2 hours)

The purpose of the lesson: Give students a diagram of a personal computer device, basic concepts and a memory and processor device.

During the classes:

1. Explanation of the new material:

Computer device from user point of view - ability to handle a computer with a tool for information processing. The computer must perceive and recognize the input information, remember it, perform various actions over it and output the results of its work, that is, to perform the main stages of information processing: input, storage, conversion, output.

To solve all these tasks, technical devices and programs are needed.

The combination of technical devices are called hardware Personal computer hardware is a system of interconnected technical devices that perform input, storage, processing and output of information.

1) Computer blocks

Personal computer consists of the following main blocks: the main memory, processor, peripheral devices. All blocks are connected with each other by the system mainstream (tire).

Highway. The exchange of information between individual devices of the computer is made by highway, connecting all computer devices.

The basis of modern architecture personal computers Put a trunk-modular principle. The modular principle allows the consumer to set the computer's configuration you want and make it upgrading if necessary. The modular organization of the computer relies on the trunk (tire) principle of sharing information between devices.

The main line (system bus) includes three multi-digit tires: data bus, address busand control bus.Tires are a largeline lines.

Data bus. On this bus, data is transmitted between various devices. For example, read from random access memory Data can be transferred to processor processing, and then the data obtained can be sent back to the storage rates. Thus, data on the data bus can be transmitted from the device to the device in any direction.

The data bus discharge is determined by the processor bit, i.e. The number of binary discharges that the processor processes in one clock. The processor discharge continuously increased with the development of computer equipment and is currently 64 bits.

Tire address. Select a device or a memory cell where you are sent or where data is read over the data bus, the processor produces. Each device or range of RAM has its own address. The address is transmitted via the address bus, and the signals are transmitted to it in one direction from the processor to RAM and devices (unidirectional tire).

Digure of the address busdefines the address space of the processor, i.e. The number of RAM cells that may have unique addresses. The number of addressed memory cells can be calculated by the formula: N.\u003d\u003e 2 7, where N is the bit of the address bus.

The bit content of the address bus is constantly increased in modern personal computers is 32 bits. Thus, the maximum possible number of addressable memory cells is: N \u003d2 32 = 4 294 967 296.

Control bus. On the control bus, signals are transmitted determining the nature of the exchange of information on the highway. The control signals determine which operation reading or record information from memory should be produced, synchronize the exchange of information between devices, etc.

Computer system block

All main components of the desktop computer are inside the system unit: a system board with a processor and RAM, storage drives on rigid and flexible disks, CD-ROM, etc. In addition, the power unit is in the system unit.

Motherboard. The main hardware component of the computer is the motherboard (Fig. 1.4). On the system board Implemented information exchange highway, there are connectors for installing a processor and RAM, as well as slots for installing external controllers.

Processor frequency, system bus and bus peripheral devices. The speed of the various components of the computer (processor, RAM and peripheral controllers) can be significantly different. To match the speed on the motherboard, special chips (chipsets) are installed, including the RAM controller (the so-called northern bridge) and the peripheral controller (southern bridge)

The North Bridge provides an exchange of information between the processor and the RAM on the system bus. The processor uses internal frequency multiplication, so the processor frequency is several times larger than the system bus frequency. In modern computers, the processor frequency may exceed the system tire frequency of 10 times (for example, the frequency of the processor 1 GHz, and the tire frequency is 100 MHz).

PCI bus is connected to the North Bridge (Peripherial Component Interconnect Bus - the interaction bus of peripheral devices), which provides the exchange of information with controllers of peripheral devices. The frequency of controllers is less than the system tire frequency, for example, if the frequency of the system bus is 100 MHz, the PCI bus frequency is usually three times less than 33 MHz. Peripheral controllers (sound card, network card, SCSI controller, internal modem) are installed in the system board expansion slots.

As the monitor's resolution and the color depth increases, the requirements for the speed of the tire connecting the video card with the processor and the RAM are increasing. Currently, a special AGP bus is usually used to connect a video message (Accelerated Graphic Port - an accelerated graphic port) connected to the northern bridge and having a frequency several times greater than the PCI bus.

The southern bridge ensures the exchange of information between the Northern Bridge and the ports for connecting peripheral equipment.

Information storage devices ( hard drives, CD-ROM, DVD-ROM) are connected to the South Bridge over the UDMA bus (ULTRA Direct Memory Access - direct memory connection).

Mouse and external modem connect to the southern bridge with serial portswhich transmit electrical impulses carrying information in machine code, sequentially one by one. Consecutive ports are referred to as som 1 and COM2, and the hardware is implemented using a 25-pin and 9-pin connectors that are derived on rear panel system unit.

The printer is connected to K. parallel portwhich provides a higher information transfer rate than serial ports, since simultaneously transmits 8 electrical pulses carrying information in machine code. The parallel port is indicated as LPT, and the hardware is implemented as a 25-pin connector on the rear panel of the system unit.

To connect scanners and digital cameras Usually used uSB port (Universal Serial Bus - Universal sequential tire), which provides high-speed connection to a computer at once several peripheral devices.

The keyboard is usually connected using the PS / 2 port.

2) Main memory

The main memory is a device for storing information. It consists of operational and permanent storage devices.

To the operational storage device (RAM), which is often also called the RAM (OP), from the disk or diskettes are copied (loaded) programs that are performed in this moment. This means that when you run any computer program on the disk, it is copied to the RAM, after which the processor begins to execute the commands set out in this program. Part of the RAM, called "video memory", contains data corresponding to the current image on the screen. When the power is turned off, the contents of RAM is erased. The speed (speed) of the computer directly depends on its RAM, which in modern computers is usually 128-256 MB. In the first models of computers, the RAM was not more than 1 MB. Modern application programs often require for its implementation of a large amount of RAM; Otherwise, they simply do not start.

A constant storage device (ROM) constantly stores information that is recorded in the manufacture of a computer. The ROM is:

• test programs checking each time the computer is turned on correct operation of its blocks;
• programs for managing the main peripheral devices - Discovery, monitor, keyboard;
• information about where the operating system is located on the disk.

The operating system is a program, managing work Computer and allowing a person to make various actions with data on disks - delete them, copy from disk to disk, run to execute various programs, etc. When you turn on the computer, the operating system is loaded into RAM and is there during the entire session. For (IWM-compatible computers, the most popular is the Windows operating system.

View of memory	Volume
RAM	32; 64; 128; 256 ... MB.
Cache	From 8 to 512 kb, 1 MB
Permanent memory
Flexible magnetic disk (diskette) - 3.5 ""
Winchester (hard magnetic disk)	20-160 ... MB
CD (CD)	250-1500 MB (650-700 MB)

The main memory consists of registers. The register is a device for interim memorizing information in digitized (binary) form. The storage element in the register is a trigger - a device that can be in one of two states, one of which corresponds to the memorization of binary zero, another to memorize the binary unit. The trigger is a tiny capacitor battery, which can be charged many times. If such a capacitor is charged - it seemed to remember the value "1" if the charge is missing - the value "O". The register contains several triggers connected with each other. The number of triggers in the register is called the computence of the computer. The performance of the computer is directly related to the bit, which is equal to 8, 16, 32 and 64.

The term "Winchester" originated from the jargon name of the first hard disk model with a capacity of 16 KB (IWM, 1973), which had 30 tracks in 30 sectors, which accidentally coincided with the Kalibrom 30 "/ 30" of the famous Hunting rifle "Winchester".

Conduct a comparison of flexible and hard disks.

Similar to flexible disks:

• the hard disk belongs to the class of media with arbitrary access to information;
• to store information, the hard disk is placed on the tracks and sectors;
• to access information, one drive engine rotates the disk package, the other installs the heads to the read / write place;
• the most common sizes of the hard disk are 5.25 and 3.5 inches in the outer diameter.

Hard drives have advantages over flexible in two main parameters:

• the volume of hard drives is significantly higher than flexible, and ranges from 20 to 120 and above GB
• the rate of information exchange is ten times more than that of flexible disks.

To access the hard disk, the name specified by any Latin letter is used, starting with C:. If installed second tough disc, he is assigned the next letter of the Latin alphabet in :, etc. For the convenience of work in operating system It is possible to conditionally break one physical disk into several independent parts using a special system program. called logic disks. In this case, each part of one physical disk is assigned its own logical name, which makes it possible to independently contact them: C:, in: etc.

The central device in the computer is cPU. It performs various arithmetic and logical operations to which the solution of any task of processing information on the computer is reduced. In addition, the processor manages the operation of all computer devices.

The processor is a device that provides information convert and control other devices of the computer.

What is a modern processor? To answer this question, we remember that the entire history of the development of computers is closely related to the achievements of humanity in the field of electronics, materials science and other areas of science and technology. It is the discovery of certain properties of materials and substances, in particular on the basis of silicon, allowed to create a processor for a modern personal computer. The modern processor is chip or chip (eng. chip - chip), made on a miniature silicon plate - crystal. So it is customary called microprocessor. IN recent models Microprocessors whose size is approximately 2 cm, contains up to several million electronic components.

Intel's modern computers are intel microprocessors, more well-known by their Pentium brand. Therefore, it is often possible to hear the name of the Pentium computer very common now, although this is just an association with one of the types of microprocessors used.

Microprocessor is constructively integral microcircuit, More precisely, speaking, a super-large integrated circuit (SBI). The word "super-largest" refers not to the size of the integrated circuit, but to the number of electronic components enclosed in it placed on a small silicon plate. The number of such components reaches several million. The more components contain a microprocessor, the higher the performance of the computer. The size of the minimum element of the microprocessor is 100 times less than the diameter of the human hair. The microprocessor has contacts in the form of pins, which are inserted into a special connector, or socket on the system board. The connector has a form of a rectangle with several rows of holes around the perimeter.

The processing of any information on the computer is associated with the processor performing various arithmetic and logical operations. Arithmetic operations - These are basic mathematical operations, such as addition, subtraction, multiplication and division. Logical operations (Logical addition, multiplication, denial, etc.) are some special operations that are most often used when verifying relations between different values. This is necessary to manage the work of the computer.

An important characteristic of the processor is its performance (The number of elementary operations performed in one second), which determines the speed of the computer as a whole. In turn, the processor performance depends on the other two of its characteristics - clock frequency and bit.

Clock frequency Specifies the rhythm of the life of the computer. The higher the clock frequency, the less the duration of operations and the higher the performance of the computer. The clock frequency determines the number of processor work clocks per second. Under tacom We understand an extremely small period of time measured by microseconds during which an elementary operation can be performed, for example, the addition of two numbers. A modern personal computer can perform millions and billions of such elementary operations per second. For the numerical expression of the clock frequency, the frequency measurement unit is used - Meghertz (MHz) is a million clocks per second. The clock frequency of modern microprocessors is more than 100 MHz.

Processor discharge Determines the size of the minimum portion of information on which the processor performs various processing operations. This portion of information is often called machine word represented by the sequence of binary discharges (bits). The processor, depending on its type, may have simultaneous access to 8, 16, 32, 64 bits.

The amount of information processed by the processor for one clutch increases with increasing bit, which leads to a decrease in the number of clocks of work required to perform complex operations. In addition, the higher the discharge, the processor can work with a large amount of memory. The first microprocessors (1971 - Intel) had a compatibility of 4 bits, a clock frequency of 108 kHz and the ability to address 640 bytes of the main memory. Modern computers Equipped with 32-bit processors, and their RAM is usually 64, 128, 256 MB.

For modern microprocessors, a tendency towards an increase in the bit and increase the clock frequency is characteristic.

	Year of issue	Frequency (MHz)	Data bus	Tire address	Addressable space
					4 GB
					4 GB
					4 GB
					4 GB
Pentium 4.

In addition to the central microprocessor, many computers have coprocessors - additional specialized processors. For example, a mathematical coprocessor is a microcircuit that helps the main processor in performing calculations when solving mathematical tasks on a computer.

The main work of the processor lies in two actions - read from the program located in the RAM, the next command and the implementation of the actions specified in this team. This action may be the execution of arithmetic and logical operations on the data, the output of information on the peripheral device and so on.

The processor consists of a control device (UU), which controls the operation of the processor using electrical signals, an arithmetic logical device (ALU), producing operations on data, and registers for temporary storage in the processor of this data and the result of the operation on them. These processor reads from RAM, it sends the result of the action on these data.

The most important processor characteristic is the clock frequency - the number of operations performed by it in 1 second (Hz). The 8086 processor produced by Intel for personal computers IWM could perform no more than 10 million operations per second, i.e. its frequency was equal to 10 MHz. The clock frequency of the 80386 processor was already 33 MHz, and the modern Pentium processor makes an average of 100 million operations per second.

Moreover, each specific processor can work no more than a certain number of RAM. For the 8086 processor, this number was only 1 MB, for the 80286 processor it increased to 16 MB, and for Pentium is 1 GB. By the way, in the computer, as a rule, there is a much smaller amount of RAM than the maximum possible processor.

The processor and the main memory are on a large board, which is called maternal. To connect various additional devices (drives, manipulators, the mouse type, printers, etc.) serve special fees - controllers. They are inserted into the connectors (slots) on the motherboard, and to their end (port), which comes out the outside of the computer, connects additional device. All computer blocks are connected by the system mainstream, or a bus, a set of wires transmitting electrical signals from one computer circuit to another.

d / s: Abstracts, messages on peripheral devices computer

Lesson 2. Basic peripherals

The purpose of the lesson: disassemble with students assigning basic computer peripheral devices, their characteristics.

During the classes:

Reiteration (At the blackboard):

1. EUM scheme.
2. Memory (RAM, ROM, Cash, Flexible Disk, Hard, CD)

Explanation of the new material.

1. Peripheral devices. Keyboard. Monitor

Peripheral devices are devices with which information or is entered into the computer, or output from it. They are also called external or input-output devices. Conditional them You can divide the main, without which the computer work is almost impossible, and others that are connected if necessary. The main devices include keyboard, monitor and drive.

The keyboard is used to enter text information. Inside it, there is a chip - a encoder - which converts a signal from the specific key to the binary code corresponding to this sign.

Monitor (display) Depending on the specific program, it works in one of two modes - text or graphic. In text mode, the screen consists of separate sites - an acquaintance. In each acquaintance, one character can be bred. In the video memory area, at this point are the data characterizing each acquaintance, the color of the symbol, the color of the background, brightness, etc. In graphical mode, the screen consists of separate points - pixels. Data in the video memory is characterized by the color of a particular pixel - this is how the image is created. The number of pixels from which the monitor screen consists is called the resolution of the monitor. The characteristics of the current monitors currently are shown in the table.

	Text mode	Graphic mode
		640x200, 2 colors; 20x200, 4 colors
	16 colors; 80x43, 16 colors	640x350,16 Flowers
	16 colors; 80x50, 16 colors	640x480, 16 colors
		640x480, 256 colors; 800x600,16 Flowers

2. Drive. Disks

To save information, it is written to special hard and flexible magnetic discs. The record is based on the ability of some materials containing basic iron, keep magnetization after short-term impact on them magnetic field. Binary zeros and units are recorded on the ring-shaped disk paths in the form of two different magnetized areas. Tracks consist of separate parts - sectors of 512 bytes. Tracks and sectors are numbered.

Magnetic disk drive (drive) consists of a motor that serves to rotate the disk and a special reading and recording magnetic head.

Hard magnetic disk (Winchester) is placed inside the computer. The volume of the hard disk can be from 10 MB to 1 GB (and this is not the limit). The computer may have a packet (several) hard drives.

Flexible magnetic discs (floppy disks) are of two types: 3-inch (3.5 "- 8 mm) and 5-inch (5.25" - 133 mm). The type is determined by the diameter of the disk located inside the plastic box. The plastic box itself performs the function of protection against external influences. The volume of the diskette depends on the density of the recording on the track that is single (30 - SD-Single Density), double (DD-Double Density), four-time (QD-Quadruply density) and high (HD-High Density), as well as on the number of workers sides on a diskette (one-sided and double-sided). The maximum floppy volume is usually indicated in its marking.

Immediately after buying a floppy disk. First, it must be formatted using the appropriate computer Program. Formatting (initialization) is the process of cutting tracks on a diskette, partitioning tracks to sectors, the stignification of special tags on them. Any floppy can be formatted to the maximum volume possible for it or any smaller volume designed for this type of floppy disk. Modern formatting programs allow you to place a floppy disk on non-standard volume (747 KB, 1.49 MB, etc.). In order for the computer to then work with such a type of diskette, you should upload a special support program. You can format and former floppy disk, while all the data on it is destroyed.

During operation, damaged, so-called failed areas may appear on the surface of the disks. The information recorded on the failed area is not read. Therefore, it should periodically check the discs special program Type Mo. The program identifies defective areas and marks them in such a way that when writing to disk, these areas are automatically skipped. In addition, the program can restore the data that falls on the failed area.

D / s: Abstracts, messages.

Lesson 3. Other peripheral devices

1. Printer

Unlike the main peripheral devices, those devices that we called others are connected to a computer depending on the specific needs of the user.

The printer is a device for outputting texts and graphic images. Currently uses several types of printers.

Matrix printer. The principle of operation of such a printer is based on the fact that the print head containing metal needles moves along the printed string. The needles at the right moment are hit by paper through the painting tape - the image is formed from individual points. The coloring tape can be wound on the coil (as in the typewriter) or laid in a special box (cartridge). Matrix printers are cheapest. The quality of printing is usually low. Print speed on average - 1 minute per page. Matrix printers are not colored.

Jet printer. In printers of this type, the smallest drops of paint are blowing on paper through tiny nozzles. These printers provide sufficiently high print quality. Print speed on average - 1 minute per page. There are colored and non-colored inkjet printers.

Laser printer. In such printers, the paint particles are transferred from a special painting drum on paper through an electric field. Print quality - high. Print speed on average - from 4 to 15 pages per 1 minute. There are colored and non-colored laser printers.

2. Other peripheral devices

The plotter (the plotter) serves to print on paper drawings. The image is created by a moving plate with a colored passenger. An ordinary plotter can output the drawing to the sheet size to A1 (841x594 mm). But there are large plotters that displays an image on a sheet with dimensions up to 3x3 m. Print speed for the A1 sheet of medium fullness - 1 hour.

The scanner is designed to enter the computer presented in the print and graphic data. Having a scanner, you can not bother, creating a drawing using graphic Editor, And quickly draw the image from the hand on the sheet of paper and enter into the computer using this device. Similarly, you can enter and handwritten text, which in the presence of the recognition program will be automatically transformed into a printed view. Scanners are manual (which is conducted on top of the sheet) and tablet (sheet is putting inside the scanner).

Streamer is a device for reserve copy Winchester data in case of their possible loss (virus, breakdown). If you use a floppy disk for this purpose, not only a lot of floppy disk, but also a lot of time. The streamer quickly writes data to the magnetic tape in a special cassette. The latest developments allow us to use conventional video tapes for this purpose.

The cursor control devices are used to quickly move the cursor on the screen. The most common among them is a mouse type manipulator (or simply "mouse"). There is a ball within it, which when moving the mouse is rolling over the surface and transmits its movement with special rollers. The signals from the rollers go to the computer. Trackball resembles a mouse, overwhelmed upside down. In motion, lead a ball fixed on the rollers. Trackball is usually used in Notebook portable computers. The joystick is a handle with buttons and applies, as a rule, for games and simulators.

Separate computers can contact each other through the telephone network. The user who connected his computer into such a network gains access to almost unlimited information. Computer signals are signals direct current. The telephone network cannot be transmitted. To convert computer signals to signals that can be transmitted via a telephone network (in other words, to modulate them - conversion A combination of sound signals of different frequencies), a special device called a modem (shortening the word modulator) is applied.

The connection of the computer with various input and output devices is carried out through ports. For some devices provided external connection To ports through connectors that are usually identified by ports. These connectors are located on the back of the system unit. Flexible, hard and laser disks Installed and connected inside the system unit. Ports are consistent and parallel.

Parallel ports

This type of ports is used to connect external devices that need to transmit a large amount of information to a close distance. Through the parallel port, 8 data bits of 8 parallel conductors are usually transmitted simultaneously. Printer, scanner are connected to the parallel port. The number of parallel ports from the computer does not exceed three, and they have, respectively, logical names LPT1, LPT2, LPTs (from the English. Printer line).

Serial ports

This type of ports is used to connect to the mouse system block, modems and many other devices. Through such port there is a serial flow of 1 bit. This can be compared with how traffic is going on along the road with one strip. Sequential data transmission is used at long distances. Therefore, serial ports are often called communication. The number of communication ports does not exceed four, and they are assigned to names from Som1 to Som4 (eng. Communication port).

3. Multimedia components

The CD-R drive is functionally similar to a disk drive, but is designed to read CDs. A CD, like a diskette, serves to store various data and audiovideoinformation presented in binary form. However, if binary numbers are presented on magnetic disks in the form of two different magnetized areas, another principle is used here. The spiral path consists of the same in length, but different in the height of the plots. To create such a form ("swelling"), the desired parts of the track "heated" the laser beam. When reading data, a lower power laser beam is used. When such a ray falls on the "strolled" section, it is reflected from its surface and enters the height. It does not fall on the low section of the beam, and therefore it is not reflected. Thus, the signals in the light receiver are presented as "1" - the presence of a signal and "O" - its absence. CDs are made of aluminum or gold and flooded in plastic. On one CD can be recorded from 650-800-900 MB of information.

SoundBlaster - device (controller fee) to convert digital audio information recorded on disks and CDs, in sounds. A amplifier can be connected to the output of the SoundBlaster sound signal and speakers to play stereo sound.

A computer equipped with a CD-ROM and SoundBlaster drive is called multimedia (multimedia - reporting in video and Audovid).

D / s: Abstract

In this lesson, we will look at what the computer is and what the computer consists of.

Personal Computer(PC, PC or EUM) is programmable electronic deviceDesigned for storing, processing and transmitting information (data). With the help of a computer, you can produce various actions: produce mathematical calculations, watch movies, listen to music, play games, write books and so on.

Now consider of what a computer consists of. The main parts of the computer can be divided into 2 groups: a system unit and external (peripheral) devices.

Composition of the system unit

The system unit is the most important part of the computer.It contains basic devices and components that allow the computer to perform actions with data. That is, it is he who is responsible for the fact that you can watch movies, play games and so on.

Physically, the system unit is a "box" of a rectangular shape. The appearance of this "drawer" is computer case.As a rule, on the front (facial) side of the case, the on and reboot buttons of the computer are located, compartments for installing CD, DVD or Blu-ray drives, as well as the processor and hard disk display buttons. In addition, connectors for connecting microphone, headphones and USB ports can be located on the front of the housing.

If you open a computer case, we will see the internal components of the system unit.

Basic components of the system unit

(CPU, CPU, stone or percent (on slang)) - the main part of the system unit and computer as a whole. It is he who performs operations and data actions, processes commands, manages other computer devices.

(Motherboard, motherboard or mammy (on slang)) - a board in which all devices or computer connectors are inserted. It is a link between all external (peripheral) and internal devices.

(GPU, Vidyuha (in Slang)) - a device that is responsible for displaying the image to the computer monitor.

(RAM, RAM (in Slang)) - the computer memory in which the commands and the data required to execute a program or applications are stored. This data processes the processor.

(HDD, hard (on slang)) - a device on which data and information is stored. All you copy to a computer (photo, music, documents) or install (programs, games) are stored on the hard disk. Also on the disk ass set the operating system.

(BP) is a block that delivers electrical energy to the components of the system unit. All components of the system unit need nutrition (energy) for work, as well as a light bulb or TV. It is in it that the cable is inserted through which the current goes out of the socket into the system unit.

Drive unit CD, DVD, Blu-ray - the device in which discs are inserted. Depending on the type of drive, the computer can perceive data from disks different types (CD, DVD, Blu-Ray)

Network and sound card.A cable is connected to the network card in order to combine several computers into a single network or to access the Internet. The sound card transmits the sound of columns. Almost all modern motherboards Already contain these cards. Buy separately sound card only if you want to connect powerful columns or acoustic system.

So we looked at what the system block of the computer consistent. In addition to the above components, there are many additional fees that can be inserted into the system unit, but they are not mandatory. We now turn to the peripheral devices.

Peripherals

Peripherals– external deviceswhich are connected to the computer system unit.

Main peripheral devices

Monitor is the most important peripheral device.Image output device . On the monitor screen we see the information. The data on the monitor comes from the video card.

Keyboard - Information entry device. Using the keyboard, we can write text.

Mouse (Mouse Manipulator) - input device. Using the mouse, we manage the cursor that runs around the screen, open the folders, run the program and so on.

Speakers- Sound output device. Through the speakers, we listen to music.

Here are 4 main peripheral devices, without which the computer cannot work.

The peripheral devices also include: microphone, headphones, printer, scanner, modem, flash drive, and so on.

So, in the first lesson, we looked at what a computer is and what it consists of. Find out what computer components are, and what is their purpose.