Graduation writing assignment
Examination paper
Issued to student of group 35 Andrey Alekseevich Romanov
Profession: “Master of Digital Information Processing”
Topic: “Writing information to removable media”
I. Descriptive part
Introduction.
1. Basic terms and concepts
2. Review of storage media, their advantages and disadvantages, principles of operation, characteristics.
4. Selecting a program for recording information to media
Conclusion.
Bibliography.
Applications.
II. Practical task
1. Create instructions for recording information on the selected removable storage medium
2. Create a job test
3. Create a presentation on your work
The task was issued by the foreman O.S. Crack
The assignment was given to student A.A. Romanov
Ministry of Education and Science of the Udmurt Republic
Autonomous professional educational institution
Udmurt Republic
"College of Radio Electronics and information technologies»
Final written qualifying work
by profession "Master of Digital Information Processing"
student of group No. 35
Subject : “Writing information to removable media”
Izhevsk, 2015
Introduction
Storage medium(information carrier) - any material object or environment containing (carrying) information that can retain information entered into/on it in its structure for a sufficiently long time. Initially, the amount of information placed on the media was small (from 128 MB to 5.2 GB). Gradually, much more information began to be placed on the media (up to 3Tb).
The main storage media: floppy disks (floppy disks), hard disk drives (hard drives), CD, DVD (including Blu-ray), flash-memory (flash drives, memory cards).
CDs and DVDs have become a part of our lives. It’s hard to imagine where we would store gigabytes of music, movies and photographs if someone had not come up with these round records with a mirror surface.
On this moment this topic is relevant because modern man is unable to live without information. But information has this peculiarity - it must be stored somewhere. There are quite a lot of information storage systems now. It can be stored on magnetic media, it can be stored on optical and magneto-optical media. But in our time, a person also faces a rather important problem - the transfer of information from one place to another, as well as the equally important problem of storing information, and as a consequence, the reliability of the media. This is why technologies related to information storage have developed so quickly.
The purpose of this final qualifying written work is:
1. Create instructions for recording information onto the selected removable storage medium.
Based on this goal, the following tasks are set:
1. Review removable media, identify their advantages and disadvantages
2. Select a program for recording to removable media
Basic terms and definitions
Information- information perceived by a person or special devices as a reflection of the facts of the material world in the process of communication.
Recording information is a way of recording information on a tangible medium.
Removable media information- a storage medium intended for its autonomous storage and use independent of the place of recording.
Media overview
FMD (Floppy Disk Media) or Floppy Disk(eng. Floppy Disk Drive) is a portable storage medium used for repeated recording and storage of data, which is a flexible magnetic disk placed in a protective plastic case (a disk with a diameter of 3.5″ has a more rigid case than a disk with a diameter of 5.25″, whereas the 8″ diameter disc is enclosed in a very flexible case) coated with a ferromagnetic layer. Floppy disks typically have a write-protect feature that allows read-only access to the data. Floppy disks were widely used from the 1970s until the end of the 1990s, giving way to more capacious and convenient CDs and flash drives at the beginning of the 21st century.
Advantages:
1. Huge recording density with small media sizes.
2. Low power consumption compared to similar media large capacity.
3. High reliability and stability.
Flaws:
1. Small recording capacity (in fact, you can’t even record one song on a disc).
2. Unreliability of information storage; the floppy disk is demagnetized under the influence of large magnetic fields.
HDD (Hard Magnetic Disk Media) or Winchester or Hard Disk(English HDD - Hard Disc Drive) is an information storage device based on the principle of magnetic recording. It is the main data storage device in most computers. It is combined with a storage device, a drive and an electronics unit and (in personal computers in the vast majority of cases) is usually installed inside the computer system unit, but there are also those connected externally.
Information is recorded on hard (aluminum or glass) plates coated with a layer of ferromagnetic material, most often chromium dioxide. HDD uses one or more plates on one axis. In operating mode, the reading heads do not touch the surface of the plates due to the layer of incoming air flow that forms near the surface during rapid rotation. The distance between the head and the disk is several nanometers (about 10 nm in modern disks), and the absence of mechanical contact ensures a long service life of the device. When the disks do not rotate, the heads are located at the spindle or outside the disk in a safe area, where their abnormal contact with the surface of the disks is excluded.
The principle of operation of hard drives is similar to the operation of tape recorders. The working surface of the disk moves relative to the read head (for example, in the form of an inductor with a gap in the magnetic circuit). When applying AC electric current(during recording) on the head coil, the alternating magnetic field that arises from the head gap acts on the ferromagnet of the disk surface and changes the direction of the domain magnetization vector depending on the signal strength. During reading, the movement of domains at the head gap leads to a change in the magnetic flux in the head magnetic circuit, which leads to the appearance of an alternating electrical signal in the coil due to the effect of electromagnetic induction.
IN Lately For reading, the magnetoresistive effect is used and magnetoresistive heads are used in disks. In them, a change in the magnetic field leads to a change in resistance, depending on the change in the magnetic field strength. Such heads make it possible to increase the likelihood of reliable information reading (especially at high information recording densities).
Advantages:
1. Allow you to write and read information many times.
2. When you turn off the computer, the information left on the hard drive is saved.
3. Large amount of stored information.
4. High reliability of data storage. The mean time between failures is about 300,000 hours, i.e. about 30 years.
Flaws:
1. It is impossible to carry it, since it is permanently attached to the system unit.
2. Relatively low performance, especially compared to RAM.
Recording methods
There are currently several recording methods:
· Longitudinal recording method.
· Perpendicular recording method.
· Thermal magnetic recording method.
Compact disc or CD(English Compact Disc) - an optical storage medium in the form of a plastic disk with a hole in the center, the process of recording and reading information is carried out using a laser. Further development CDs became DVDs (more on them later).
The CD was originally created to store audio recordings in digital form, but later became widely used as a medium for storing any data in binary form.
CD-ROM(English: Compact Disc Read-Only Memory, read: “sidi-rom”) - a type of CD with data recorded on them that is read-only (read-only memory - read-only memory). CD-ROM is a modified version of CD-DA (disk for storing audio recordings), allowing you to store other digital data on it (physically it is no different from the first one, only the format of the recorded data has been changed). Later, versions were developed with the ability to both write once (CD-R) and rewrite multiple times (CD-RW) information on a disk. A further development of CD-ROM drives was DVD-ROM drives.
CD-ROMs- popular and cheapest means of distribution software, computer games, multimedia and other data. CD-ROM (and later DVD-ROM) became the main medium for transferring information between computers, displacing the floppy disk from this role (it is now giving way to more promising solid-state media).
The CD-ROM recording format also provides for recording mixed content information onto one disc - simultaneously both computer data (files, software, readable only on a computer), and audio recordings (played on a regular audio CD player), video, texts and pictures. Such discs, depending on the order of the data, are called Enhanced CDs or Mixed-Mode CDs.
CD-R(Compact Disc-Recordable) is a type of compact disc (CD) developed by Philips and Sony for recording information once. CD-R supports all the features of the Red Book standard and, in addition, allows you to record data.
A regular CD-R is a thin disk made of transparent plastic (polycarbonate) 1.2 mm thick, 120 mm in diameter (standard), weight 16-18 g. or 80mm (mini). The capacity of a standard CD-R is 74 minutes of audio or 650MB of data. However, at the moment the standard capacity of a CD-R can be considered 702MB of data or 79 minutes 59 seconds and 74 frames.
The polycarbonate disk has a spiral track to guide the laser beam when writing and reading information. On the spiral track side, the disc is covered with a recording layer consisting of a very thin layer of organic dye, then a reflective layer of silver, its alloy or gold. This layer is already covered with a protective photopolymerizable varnish and cured with ultraviolet radiation. And already on this protective layer various inscriptions are applied with paint.
A CD-R always has a service track with servo marks ATIP - Absolute Time In Pregroove - absolute time in the service track. This service track is needed for the tracking system, which keeps the laser beam while recording on the track and monitors the recording speed. In addition to synchronization functions, the service track also contains information about the manufacturer of this disc, information about the material of the recording layer, the length of the track to be recorded, etc. The service track is not destroyed when data is written to the disk, and many copy protection systems use it to to distinguish the original from the copy.
CD-RW(English Compact Disc-ReWritable, Rewritable CD) - a type of compact disc (CD), developed in 1997 for repeated recording of information
CD-RW is a logical development of CD-R, however, unlike it, it allows data to be rewritten many times. This format was introduced in 1997 and during its development was called CD-Erasable (CD-E, Compact Disc Erasable). CD-RW is similar in many ways to CD-R, but its recording layer is made of a special chalcogenide alloy, which, when heated above its melting point, transforms from a crystalline state of aggregation to an amorphous one.
DVD(eng. Digital Versatile (Video) Disc - digital multi-purpose (video) disk) - an information carrier made in the form of a disk, the size of a CD, but with a denser working surface structure, which allows you to store and read a larger amount of information in due to the use of a laser with a shorter wavelength and a lens with a larger numerical aperture.
The first discs and DVD players appeared in November 1996 in Japan and March 1997 in the United States.
In the early 1990s, two standards were being developed for high-density optical media. One of them was called Multimedia Compact Disc (MMCD) and was developed by Philips and Sony, the second - Super Disc - was supported by 8 large corporations, including Toshiba and Time Warner. Later, the efforts of the standards setters were united under the leadership of IBM, which did not want a repeat of the format war, as was the case with the VHS and Betamax cassette standards in the 1970s. The DVD was officially announced in September 1995, when the first version of the DVD specifications was published. Changes and additions to the specifications are made by the DVD Forum (formerly called the DVD Consortium), whose members are 10 founding companies and more than 220 individuals.
The DVD-R(W) recording standard was developed in 1997 by the Japanese company Pioneer and a group of companies that joined it and were included in the DVD Forum as the official specification for recordable (and subsequently rewritable) discs.
Based on DVD-R discs DVD-RW initially had the problem that older drives were incompatible with these new discs (the problem was the difference in the optical layer responsible for “storing” information, which had less reflectivity (compared to write-once media and stamped discs) . Further this problem was almost completely resolved, although previously it was precisely because of this that old DVD drives could not normally play new rewritable discs.
An alternative format was created, called DVD+R, which had a different reflective layer material and special markings that made it easier to position the head - the main difference between such “plus” discs and “minus” ones. With this, DVD+RW discs are able to record (over the existing one) in several steps, as in a conventional video cassette recorder, eliminating the tedious preliminary erasing of all content (for DVD-RW, you first need to completely erase the existing recording).
In addition, when using rewritable “plus” discs, the number of errors decreases and the recording accuracy increases, as a result of which bad sector can be easily rewritten rather than erasing or re-recording the entire disc. Therefore, if you intend to actively use the dubbing and recording function, it is better to choose a recorder that supports the “plus” format (which most models are now capable of).
DVD-Video
To play DVDs with video, you need a DVD optical drive and an MPEG-2 decoder (that is, either a household DVD player with a hardware decoder, or a computer DVD drive and a software player with a decoder installed). DVD movies are compressed using the MPEG-2 algorithm for video and various (often multi-channel) formats for audio. Compressed video bitrate varies from 2000 to 9800 Kbps, often variable (VBR). Standard size A video frame of the PAL standard is 720×576 pixels, and an NTSC standard is 720×480 pixels.
The audio data in a DVD movie can be in PCM, DTS, MPEG, or Dolby Digital (AC-3) format. In countries that use the NTSC standard, all DVD movies must contain a PCM or AC-3 soundtrack, and all NTSC players must support these formats. Thus, any standard disc can be played on any standard hardware.
Blu-ray Disc, BD(English blue ray - blue ray and disc - disk; writing blu instead of blue is intentional) - an optical media format used for high-density recording and storage of digital data, including high-definition video. The Blu-ray standard was jointly developed by the BDA consortium. The first prototype of the new carrier was presented in October 2000. The modern version was presented at the international consumer electronics exhibition Consumer Electronics Show (CES), which was held in January 2006. The commercial launch of the Blu-ray format took place in the spring of 2006.
Blu-ray gets its name from the use of a short-wavelength (405 nm) "blue" (technically blue-violet) laser for recording and reading. The letter "e" was deliberately omitted from the word "blue" to allow registration trademark, since the expression "blue ray" is commonly used and cannot be registered as a trademark.
From the advent of the format in 2006 until the beginning of 2008, Blu-ray had a serious competitor - the alternative format HD DVD. Within two years, many of the major film studios that had originally supported HD DVD gradually switched to Blu-ray. Warner Brothers, the last company to release its products in both formats, phased out HD DVD in January 2008. On February 19 of the same year, Toshiba, the creator of the format, stopped development in the field of HD DVD.
Flash memory
Flash memory(English flash memory) - a type of solid-state semiconductor non-volatile rewritable memory (EPPROM).
It can be read as many times as desired (within the data storage period, typically 10–100 years), but it can be written to only a limited number of times (maximum - about a million cycles). Flash memory is common and can withstand about 100 thousand rewrite cycles, much more than a floppy disk or CD-RW can withstand. It does not contain moving parts, so, unlike hard drives, it is more reliable and compact.
Due to its compactness, low cost and low power consumption, flash memory is widely used in digital portable devices- photo and video cameras, voice recorders, MP3 players, PDAs, mobile phones, as well as smartphones and communicators. In addition, it is used to store firmware in various devices(routers, mini-PBX, printers, scanners, modems), various controllers. Also recently, USB flash drives (flash drive, USB drive, USB disk) have become widespread, practically replacing floppy disks and CDs.
At the end of 2008, the main drawback that prevents devices based on flash memory from displacing hard drives from the market is the high price/volume ratio, which exceeds this parameter in hard drives 2–3 times. In this regard, the volumes of flash drives are not so large, but work is underway in these directions. Cheaper technological process, competition is intensifying. Many companies have already announced the release of SSD drives with a capacity of 256 GB or more.
This type of flash memory is based on a NOR element because in a floating gate transistor, a low voltage at the gate denotes a one.
The transistor has two gates: control and floating. The latter is completely isolated and is capable of retaining electrons for up to 10 years. The cell also has a drain and a source. When programming with voltage, an electric field is created at the control gate and a tunnel effect occurs. Some electrons tunnel through the insulator layer and reach the floating gate. The charge on the floating gate changes the "width" of the drain-source channel and its conductivity, which is used for reading.
Programming and reading cells have very different power consumption: flash memory devices consume quite a lot of current when writing, while the energy consumption is low when reading.
To erase information, a high negative voltage is applied to the control gate, and electrons from the floating gate move (tunnel) to the source.
In the NOR architecture, each transistor must be connected to an individual contact, which increases the size of the circuit. This problem is solved using NAND architecture.
The NAND type is based on the NAND element. The operating principle is the same; it differs from the NOR type only in the placement of the cells and their contacts. As a result, it is no longer necessary to make an individual contact to each cell, so the size and cost of the NAND chip can be significantly reduced. Also writing and erasing is faster. However, this architecture does not allow access to an arbitrary cell.
NAND and NOR architectures now exist in parallel and do not compete with each other, since they are used in different areas of data storage.
Types of memory cards
· CF(Compact Flash)
· MMC(Multimedia Card)
· RS-MMC(Reduced Size Multimedia Card)
· DV-RS-MMC(Dual Voltage Reduced Size Multimedia Card)
· MMC-micro
· SD Card(Secure Digital Card)
· SDHC(SD High Capacity, SD high capacity)
· MiniSD(Mini Secure Digital Card)
· MicroSD(Micro Secure Digital Card)
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Technical information media include paper media (punched cards, punched tapes), film and photographic materials (microfilms, films, etc.), magnetic media (disks, tapes), video discs, video films, printouts of data and programs on printers, information on screens Computers, industrial television installations, display boards for individual and collective use and others. The danger of technical media is determined by the high growth rates of the fleet technical means and personal computers in operation, their widespread use in various spheres of human activity, the high degree of concentration of information on technical media and the scale of people’s participation in the use of these media in practical activities. To work with external memory It is necessary to have a storage device (a device that provides recording and (or) reading of information) and a storage device - media. Main types of storage devices: floppy magnetic disk drives (FMD); hard magnetic disk drives (HDD); magnetic tape drives (NML); CD-ROM, CD-RW, DVD drives.
The main types of media correspond to them:
flexible magnetic disks (Floppy Disk) (diameter 3.5'' and capacity 1.44 MB; diameter 5.25'' and capacity 1.2 MB (currently obsolete and practically not used, production of drives designed for disks with a diameter 5.25'', also discontinued)), disks for removable media;
hard magnetic disks (Hard Disk);
cassettes for streamers and other NML;
CD-R discs OM, CD-R, CD-RW, DVD.
Storage devices are usually divided into types and categories in connection with their operating principles, operational, technical, physical, software and other characteristics. For example, according to the operating principles, the following types of devices are distinguished: electronic, magnetic, optical and mixed - magneto-optical. Each type of device is organized on the basis of the corresponding technology for storing/reproducing/recording digital information. Therefore, in connection with the type and technical design of the information carrier, they distinguish: electronic, disk and tape devices.
Main characteristics of drives and media:
information capacity; speed of information exchange; reliability of information storage; cost.
Disk devices divided into flexible (Floppy Disk) and hard (Hard Disk) drives and media. The main property of disk magnetic devices is the recording of information on a medium on concentric closed tracks using physical and logical digital encoding of information. The flat disk media rotates during the reading/writing process, which ensures servicing of the entire concentric track; reading and writing is carried out using magnetic read/write heads, which are positioned along the radius of the media from one track to another.
For the operating system, data on disks is organized into tracks and sectors. The tracks (40 or 80) are narrow concentric rings on the disk. Each track is divided into parts called sectors. When reading or writing, the device always reads or writes an integer number of sectors, regardless of the amount of information requested. The sector size on a floppy disk is 512 bytes. A cluster (or data cell) is the smallest area of a disk that can be operating system used when writing a file. Typically a cluster is one or more sectors. Removable media is used quite often. A fairly popular storage device is Zip. It is available as integrated or stand-alone units connected to a parallel port. These drives can store 100 and 250 MB of data on cartridges resembling a 3.5” floppy disk, provide an access time of 29 ms and data transfer speeds of up to 1 MB/s. If a device is connected to the system via a parallel port, then the data transfer rate is limited by the speed of the parallel port.
The Jaz drive is a type of removable hard disk drive. The capacity of the cartridge used is 1 or 2 GB. The disadvantage is the high cost of the cartridge. Main Application - backup data.
In magnetic tape drives (most often such devices are streamers), recording is done on mini-cassettes. The capacity of such cassettes is from 40 MB to 13 GB, the data transfer speed is from 2 to 9 MB per minute, the tape length is from 63.5 to 230 m, the number of tracks is from 20 to 144.
CD-ROM is a read-only optical storage medium that can store up to 650 MB of data. Accessing data on a CD-ROM is faster than data on floppy disks, but slower than on hard drives. CD-ROM is a one-way storage medium. More popular are CD-RW drives, which allow you to write and rewrite CD-RW discs, write CD-R discs, read CD-ROM discs, i.e. are in a certain sense universal.
The abbreviation DVD stands for Digital Versatile Disk, i.e. universal digital disk. Having the same dimensions as a regular CD and a very similar operating principle, it holds an extremely large amount of information - from 4.7 to 17 GB. Perhaps it is precisely because of its large capacity that it is called universal. True, today the DVD disc is actually used in only two areas: for storing video films (DVD-Video or simply DVD) and ultra-large databases (DVD-ROM, DVD-R).
26-27.input/output device- a component of a standard computer architecture that provides the computer with the ability to interact with the outside world and, in particular, with users and other computers.
Divided into:
---Input device:-Input Devices graphic information Scanner, Video and Web camera, Digital camera, Video capture card, Microphone, Digital voice recorder
Text input devices: Keyboard
Pointing devices: Mouse, Trackball, Trackpoint, Touchpad, Joystick, Roller Mouse, Graphics tablet, Light pen, Analog joystick, Touchscreen
Gaming input devices: Joystick, Pedal, Gamepad, Steering wheel, Flight simulator lever (wheel, Airplane control stick), Dance platform
---Output device-Devices for outputting visual information: Monitor (display), Projector, Printer, Plotter, Optical drive with disc marking function, LEDs (on system unit or laptop, for example, informing about disk read/write)
Audio output devices: Built-in speaker, Speakers, Headphones
---I/O devices: Magnetic drum , Streamer , Drive , HDD , Various ports , Various network interfaces.
Channels input-output channel (English IOC - input-output channel), hereinafter referred to as IOC, and interfaces provide interaction central devices machine and peripheral devices.
KVVs are logically independent devices that operate under the control of their own programs located in memory.
KVV and interfaces perform the following functions
Allows you to have machines with a variable composition of peripheral devices.
Ensure parallel operation of peripheral devices both among themselves and in relation to the processor.
Provide automatic recognition and response of the processor to various situations arising in peripheral devices.
Multiplex channel
The channel itself is fast, but serves a slow peripheral device. At the same time, having connected to one device, it sends one machine word, and after that connects to another.
Selector channel
The channel is fast and serves fast devices. At the same time, having connected to one device, it transmits all the information, and after that it connects to another device.
28. Keyboard, key assignments- a computer device that is located in front of the display screen and is used for typing text and controlling the computer using the keys on the keyboard.
All keys can be divided into several groups:
alphanumeric keys; function keys; control keys; cursor keys;
number keys. In the center are alphanumeric keys, very similar to the keys of a regular typewriter. They have numbers on them, Special symbols(“!”, “:”, “*”, etc.), letters of the Russian alphabet, Latin letters. Using these keys you will type all kinds of texts, arithmetic expressions, and write down your programs. At the bottom of the keyboard there is a large key without symbols on it - “Space”. "Space" is used to separate words and expressions from each other. Russian keyboards are bilingual, so their keys have characters from both the Russian and English alphabets. In the Russian language mode, texts are typed in Russian, English - in English. The alphanumeric keyboard is the main part of the keyboard with the alphanumeric keys on which the characters are drawn, along with all the closely adjacent control keys. The function keys F1 – F12, located at the top of the keyboard, are programmed to perform certain actions (functions). So, very often the F1 key is used to call up help.
To move the cursor, use the cursor keys; they have arrows pointing up, down, left, and right. These keys move the cursor one position in the corresponding direction. The PageUp and PageDown keys allow you to “scroll” the document up and down, and the Home and End keys move the cursor to the beginning and end of the line.
The Esc key is located in top corner keyboards. Usually serves to abandon an action just performed.
The Shift, Ctrl, alt keys correct the actions of other keys.
Numeric keys – when the Num Lock indicator is on, a convenient keypad with numbers and arithmetic symbols is available. Arranged like a calculator. If the Num Lock indicator is off, then cursor control mode works
29, Memory devices, computer classification, principle of operation, basic characteristics. storage device - a storage medium intended for recording and storing data. The operation of a storage device can be based on any physical effect that brings the system to two or more stable states.
Classification storage devices
Based on the stability of recording and the possibility of rewriting, memories are divided into: - Permanent storage (ROM), the contents of which cannot be changed by the end user (for example, BIOS). ROM in operating mode allows only reading information. ---Writable memory (PROM), in which the end user can write information only once (for example, CD-R).---Multiple-rewritable memory (PROM) (for example, CD-RW).--Run-access memory (RAM) ) provide a mode for recording, storing and reading information during its processing. Fast but expensive RAM (SRAM) is built on flip-flops, while slower but cheaper types of RAM - dynamic memory (DRAM) are built on capacitors. In both types of memory, information disappears after disconnection from the power source (for example, current).
By type of access, storage devices are divided into: - Sequential access devices (for example, magnetic tapes). - Random access (RAM) devices (for example, random access memory). - Direct access devices (for example, hard magnetic disks). .---Devices with associative access (special devices to increase database performance) By geometric design:--disk (magnetic disks, optical, magneto-optical);---tape (magnetic tapes, punched paper tape);--drum (magnetic drums );--card (magnetic cards, punched cards, flash cards, etc.)---printed circuit boards (DRAM cards, cartridges).
According to the physical principle: - perforated (with holes or cutouts) – punched card ===punched tape==with magnetic recording ==ferrite cores==magnetic disks ==Hard magnetic disk==Floppy magnetic disk==magnetic tapes==magnetic cards =optical ==CD==DVD==HD-DVD==Blu-ray Disc
Main characteristics of the memory
The most important characteristics of a memory are information capacity and speed.
The information capacity of a memory is determined by the number of units of information that can be stored in it. As a rule, information capacity refers only to the useful volume of stored information; it does not include the size of memory occupied by service information, for example, reserve areas, sync tracks, engineering cylinders, etc. The performance of the memory is characterized by its timing characteristics, which include:
The access time (cycle time) characterizes the maximum frequency of access to a given memory when reading or writing information. The time for reading (sampling) information is the time interval for accessing the memory from the submission of the read signal to the receipt of the output signal. Information recording time is the time interval from the moment the signal is sent to access the memory until the moment the memory is ready to receive the next piece of information. Important characteristics of the charger are also reliability, device weight, dimensions, power consumption and cost.
30, Microprocessors,their characteristics, controllers. Microprocessor - processor (device responsible for performing arithmetic, logical operations and control operations written in machine code), implemented as a single chip or a set of several specialized chips (as opposed to implementing a processor in the form electrical diagram on element base general purpose or in the form program model). The first microprocessors appeared in the 1970s and were used in electronic calculators. Soon they began to be built into other devices, such as terminals, printers and various automation systems. Affordable 8-bit microprocessors with 16-bit addressing enabled the creation of the first consumer microcomputers in the mid-1970s. Microprocessors are characterized by: 1) clock frequency, which determines the maximum execution time for switching elements in a computer;
2) bit depth, i.e. the maximum number of simultaneously processed binary bits. 3) architecture. The concept of microprocessor architecture includes a system of commands and addressing methods, the ability to combine the execution of commands in time, the presence of additional devices in the microprocessor, principles and modes of its operation .Microcontroller(eng. Micro Controller Unit, MCU) - a microcircuit designed to control electronic devices. A typical microcontroller combines the functions of a processor and peripheral devices and contains RAM or ROM. Essentially, it is a single-chip computer capable of performing simple tasks. The most important characteristics of a microprocessor are:
31. Microcomputers and their classes. Computers of this class are available to many enterprises. Organizations using microcomputers usually do not create computer centers. To maintain such a computer, they only need a small computing laboratory consisting of several people. The staff of a computing laboratory necessarily includes programmers, although they are not directly involved in program development. Required system programs usually purchased together with a microcomputer, and the development of the necessary application programs is ordered to larger computer centers or specialized organizations. The following classification of microcomputers can be given: -- Universal -- Multi-user microcomputers are powerful microcomputers equipped with several video terminals and operating in time-sharing mode, which allows several users to work effectively on them at once. -- Personal computers (PCs) are single-user microcomputers that meet the requirements of general accessibility and versatility of use, designed for one user and controlled by one person - Laptop computers are usually needed by business leaders, managers, scientists, journalists who have to work outside the office - at home, at presentations or in business trip time.
Main types of laptop computers:
Laptop. It is close in size to a regular briefcase. In terms of basic characteristics (speed, memory) it is approximately the same as a desktop PC. Now computers of this type are giving way to even smaller ones.
Notebook. It is closer in size to a large format book. It weighs about 3 kg. Fits in a briefcase. To communicate with the office, it is usually equipped with a modem. Laptops often come with CD-ROM drives. Many modern laptops include interchangeable units with standard connectors. You can insert a CD drive, a magnetic disk drive, a spare battery, or a removable hard drive into the same slot as needed. The laptop is resistant to power failures. Even if it receives energy from a regular power supply, in case of any failure it instantly switches to battery power.
Palmtop (handheld) - the smallest modern personal computers. Fits in the palm of your hand. Magnetic disks are replaced by non-volatile electronic memory. There are no disk drives either - information exchange with regular computers goes to communication lines.
Despite the relatively low performance compared to large computers, microcomputers are also used in large computer centers. There they are entrusted with auxiliary operations for which there is no point in using expensive supercomputers. Such tasks, for example, include preliminary preparation data.
Servers are multi-user powerful microcomputers in computer networks, dedicated to processing requests from all network stations. Servers are usually classified as microcomputers. Server - dedicated to processing requests from all stations computer network a computer that provides these stations with access to shared system resources (computing power, databases, program libraries, printers, faxes, etc.) and distributes these resources.
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Educational:
· Contribute to the formation of a system of knowledge, skills and abilities in the field of information and communication technologies used in education.
· Introduce modern digital media.
· Consider ways of interaction between a teacher and subjects of the pedagogical process and representatives of the professional community in a network information environment.
Educational:
· Develop and stimulate student research activities.
· Develop the ability to evaluate the benefits, limitations and selection of hardware to solve professional and educational problems.
· Contribute to the improvement of professional knowledge and skills by using the capabilities of the information environment.
Educational:
· Form motivation for information pedagogical activities.
II. Flash memory.
III. Optical discs.
IV. Hard disks.
V. SDRAM chips.
I. Modern digital media.
As a rule, multimedia fragments occupy a large amount of computer memory. And while storing large amounts of information on a computer, in particular on a Web server, does not cause any particular problems, transferring large amounts of information can take a very long time. For example, transferring information with a volume of 20 megabytes through a modem operating at a speed of 56 kilobits per second over the Internet will take almost an hour. Of course, information can be compressed and thereby reduce transmission time. However, they are best suited for storing and transporting multimedia educational programs laser discs, which are widely used today and are known as CD-ROMs.
The most common memory devices at present:
§ Flash memory: USB drives, memory cards in phones and cameras, SSD
§ Optical discs: CD, DVD, Blu-Ray, etc.
§ Hard drives (HDD)
§ SDRAM chips (DDR and XDR)
The main parameters of the memory include information capacity (bits), power consumption, information storage time, and performance.
II. Flash memory(English) flashmemory) is a type of semiconductor electrically reprogrammable memory (EEPROM) technology. Due to its compactness, low cost, mechanical strength, large capacity, speed and low power consumption, flash memory is widely used in digital portable devices and storage media.
Specific external conditions can catastrophically shorten the storage life of data. For example, elevated temperatures or radiation (gamma ray and high-energy particle) exposure.
The erase speed varies from units to hundreds of milliseconds depending on the size of the erased block. The recording speed is tens to hundreds of microseconds.
Typically, the read speed for NOR chips is rated at tens of nanoseconds. For NAND chips, the read speed is tens of microseconds.
There are two main uses of flash memory: as a mobile storage medium and as a storage for software (“firmware”) of digital devices. Often these two applications are combined in one device.
Flash memory allows you to update the firmware of devices during operation.
