Bryakotnin Nikolay Aleksandrovich

National research Irkutsk state technical university, Russia

FUNCTION PRINCIPLE AND ARCHITECTURE OF THE COMPUTER

Problem statement. The computer is a programmable electronic device that can manipulate data and perform calculations, and perform other tasks to manipulate symbols. We constantly use computers and do not even think about their internal design, so I would like to take a look more closely at principles of computers.

Key findings. Computer-based forms machinery (HardWare), built mainly through electronic and electromechanical components and devices. The principle of operation is to run computer programs (SoftWare) - pre-designed, well-defined sequences of arithmetic, logical, and other operations.

Any computer program is a series of individual commands. Command - a description of the operations to be performed by the computer. As a rule, the command has its own code, input data and results. The result produced by the command of well-defined rules for the command, by the design of the computer. The set of commands executed by this computer, called the machine-instruction code. Computers operate at very high speeds, in the millions - hundreds of millions of operations per second.

A variety of modern computers is very high. However, their structures are based on common logical principles to allocate any computer device connected to communication channels through which information is transmitted:

1. The input device - a device that translate information from human language into machine language.

2. The output device - a device that translate information from the machine language in a form accessible to human perception

3. The memory (storage device, memory). Computer memory is built from binary storage elements - bits in groups of 8 bits called bytes. All bytes are numbered. Byte number called its address. The bytes can be combined in a cell, which are also called words. Each computer has its specific characteristic length of the word - two, four or eight bytes. This does not preclude the use of the memory cells of a different length. Variable formats are permitted for information.

4. Processor. That part of the processor that executes the command is called an arithmetic logic unit (ALU) and the other part, which serves as the control device, called a control unit (CU). Typically, these two devices are allocated arbitrarily, they are not structurally separated.

As part of the processor has a number of additional specialized memory cells called registers. Register serves as a short-term storage or the number of commands. Over the contents of some registers special electronic circuits can perform some manipulation. The main element of the register is an electronic circuit called a flip-flop, which is able to store one binary digit. Register is a set of flip-flops interlocked with each other in a certain way a common control system.

Central Processing Unit (CPU, from the English. Central Processing Unit) - is the main component of a working computer that performs arithmetic and logic operations, a given program, it controls the computing process and coordinates the work of all the devices in the computer.

The CPU generally comprises:

· an arithmetic logic unit;

· data bus and address bus;

· registers;

· counter;

· cache - a very small amount of fast memory (8 to 512 KB);

· math coprocessor floating point numbers.

Modern processors run in a microprocessor. Physically, the microprocessor is co-featured bout integrated circuit - crystalline silicon thin plate rectangular area of a few square millimeters, which are placed on the circuit that implements all the functions of the processor. The crystal plate is typically placed in a plastic or ceramic body and connects the flat wires with gold metal pins, so it can be connected to the mainboard. The computing system may have multiple processors operating in parallel. Such systems are called multiprocessor.

It is assumed that to distinguish architecture and structure of the computer devices. Computer architecture called its description on a general level, including a description of the user programming capabilities, system commands, system addressing, memory organization, etc. Architecture defines the principles of action, information communication and interconnection of basic logical node computer: processor, operative memory, external memory and peripheral devices. The generality of the architecture of different computer provides compatibility with the user's perspective. Structure of the computer - it is a set of functional elements and relationships between them. Items can be a variety of devices - from basic logical node computer to a simple scheme. Structure computer graphically represented in block diagram form that can be used to describe computer at any level of granularity.

The most common architectural solutions:

• Classical architecture (von Neumann architecture) - a single arithmetic logic unit (ALU), through which the flow of data, and one control unit (CU), through which the stream of instructions - the program. This is single-processor computer. This type of architecture provides personal computer architecture and a common bus. All function blocks are connected by a common bus, also known as the system highway. Physically highway is multiple lines with sockets for connecting electronic circuits. The set of wire line is divided into separate groups: an address bus, data bus and control bus. Peripheral devices (printer, etc.) connected to the computer through special hardware controllers - control device peripherals. Controller - a device that connects the peripheral equipment or communication channels with the central processor, freeing the CPU from the direct control of the operation of the equipment.

• Multiprocessor architecture. The presence of multiple processors in a computer means may be arranged in parallel multiple data streams and many commands. Thus, in parallel can be performed several fragments of a problem.

• Multicomputer system. Here are a few processors belonging to the computer system does not have a common memory, and each have their (local). Every computer in the multicomputer system has a classical architecture, and such a system is used widely. However, the effect of the use of such a computer system can be accessed only in solving problems with a very special structure: it should be broken up into many loosely connected subs how many computers in the system.

• The architecture of parallel processors. Here are a few ALU running a CU. This means that the set of data can be handled by one program - that is, one instruction stream. High performance of this architecture can be obtained only on the tasks in which the same computing operations are performed simultaneously on different data sets of the same type.

The advantage in speed multiprocessor and multicomputer systems to uniprocessor is obvious. In modern machines often have elements of different types of architectural solutions. There are also architectural solutions that are radically different from those discussed above.

Conclusion. In conclusion, I would like to add that personal computers are the main components of information technology and systems. Each person must be guided freely in the structure of the computer, to know, evaluate and select those tools that will be most efficient to solve emerging problems.

Литература

1. Guzenko E.N. Personal Computer. Publishing house: «Astrel». 2011 g. 546 p.

2. Zaharov V.V. The newest tutorial on personal. Publishing house: «RIPOL classic». 2008 g. 355 p.