Technical media include paper media (punched cards, punched tapes), cinema, photo 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, individual and collective displays, and others. The danger of technical media is determined by the high growth rate of the fleet of technical equipment and PCs that are in operation, their widespread use in various fields 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 drive (a device that provides recording and (or) reading information) and a storage device - carrier. The main types of drives: floppy disk drives (HMD); drives on hard magnetic disks (HDD); tape drives (NML); CD-ROM, CD-RW, DVD drives.
They correspond to the main types of media:
flexible magnetic disks (Floppy Disk) (with a diameter of 3.5 `` and a capacity of 1.44 Mb; with a diameter of 5.25 '' and a capacity of 1.2 Mb (currently outdated and practically not used, production of drives intended for disks with a diameter 5.25 '', also discontinued)), disks for removable media;
hard magnetic disks (Hard Disk);
cartridges for streamers and other NML;
cD-R discsOM, 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. So, 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 storage / playback / recording technology. digital information. Therefore, in connection with the type and technical design of the storage medium, there are: electronic, disk and tape devices.
The main characteristics of drives and media:
information capacity; speed of information exchange; reliability of information storage; cost.
Disk devices are 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 onto concentric closed tracks using physical and logical digital coding of information. Flat disk media rotates during reading / writing, which ensures the maintenance of the entire concentric track, reading and writing is carried out using magnetic read / write heads, which are positioned along the radius of the medium from one track to another.
For the operating system, disk data 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 diskette is 512 bytes. A cluster (or data location cell) is the smallest disk area that operating system uses when writing a file. Typically, a cluster is one or more sectors. quite often use removable media. A fairly popular drive is Zip. It is available as built-in or stand-alone units connected to the 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 a data transfer rate of up to 1 Mb / s. If the device connects to the system through a parallel port, then the data transfer rate is limited by the speed of the parallel port.
Type of removable drives hard drives refers to the Jaz drive. The capacity of the cartridge used is 1 or 2 GB. The disadvantage is the high cost of the cartridge. The main application is backup data.
In drives on magnetic tapes (most often streamers act as such devices) recording is made 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. Access to data on a CD-ROM is faster than data on a floppy disk, but slower than on a hard disk. CD-ROM is a one-way storage medium. The most popular are CD-RW drives, which allow you to burn and rewrite CD-RW discs, burn CD-Rs, read CD-ROMs, i.e. are in a 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 principle of operation, it holds an extremely large amount of information - from 4.7 to 17 GB. Perhaps it is because of the large capacity that it is called universal. True, for today, a DVD-ROM is really used only in two areas: for storing videos (DVD-Video or just DVD) and extra-large databases (DVD-ROM, DVD-R).
26-27 input-output device - a component of a typical computer architecture that provides a computer with the ability to interact with the outside world and, in particular, with users and other computers.
Subdivided into:
---Input device: -Graphic information input devices Scanner, Video and Webcam, Digital camera, Video capture card, Microphone, Digital voice recorder
Text Input Devices: Keyboard
Pointing (coordinate) devices: Mouse, Trackball, Trackpoint, Touchpad, Joystick, Roller Mousе, Graphic tablet, Light pen, Analog joystick, Touchscreen
Game input devices: Joystick, Pedal, Gamepad, Steering wheel, Lever for flight simulators (steering wheel, Aircraft control knob), Dance platform
---Output device -Devices for outputting visual information: Monitor (display), Projector, Printer, Plotter, Optical drive with the function of marking disks, LEDs (on the system unit or laptop, for example, informing about reading / writing to the disk)
Audio Output Devices: Built-in Speaker, Speakers, Headphones
---Input / output devices:Magnetic drum , Streamer , Drive , HDD , Various ports , Various network interfaces.
Channels input-output (English IOC - input-output channel), hereinafter referred to as HWB, and interfaces provide interaction between the central devices of the machine and peripherals.
KVV - logically independent devices that operate under the control of their own programs in memory.
HMI and interfaces perform the following functions
They allow you to have machines with a variable composition of peripheral devices.
Provide 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 that arise in peripheral devices.
Multiplex channel
The channel itself is high-speed, but serves a slow peripheral device. At the same time, having connected to one device, it submits one machine word, and after that it is connected to another.
Selector channel
The channel is fast and serves fast devices. At the same time, connecting to one device, transfers all the information, and then connects to another device.
28. Keyboard, assignable key - a computer device, which is located in front of the display screen and serves for typing 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 are marked with numbers, special characters ("!", ":", "*", Etc.), letters of the Russian alphabet, Latin letters. Using these keys you will type all kinds of texts, arithmetic expressions, write down your programs. At the bottom of the keyboard is big key without characters on it - "Space". "Space" is used to separate words and expressions from each other. Russian keyboards are bilingual, so the keys of both Russian and English alphabets are drawn on their keys. In the Russian language mode, texts are typed in Russian, English - in English. The alphanumeric keyboard is the main part of the keyboard with alphanumeric keys on which the characters are drawn, together with all closely adjacent control keys. 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 help.
To move the cursor, use the cursor keys, they show 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 the upper corner of the keyboard. Usually serves to discard the action just taken.
The Shift, Ctrl, alt keys adjust the actions of other keys.
Numeric keys - when the Num Lock indicator is on, a convenient keypad with numbers and signs of arithmetic operations. Arranged as on a calculator. If the Num Lock indicator is off, the cursor control mode works
29, Storage device computer class., The principle of operation, osn.khar-ki. storage device - a storage medium for recording and storing data. The operation of the storage device may be based on any physical effect that ensures the system is brought into two or more stable states.
Classificationstorage devices
According to the stability of the recording and the possibility of overwriting the memory, they are divided into: - Permanent memory (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 (EPROM), in which the end user can write information only once (for example, CD-R) .--- Repeatedly rewritable memory (EEPROM) (for example, CD-RW) .-- Operational memory (RAM ) provide a mode of recording, storage and reading of information during its processing. Fast, but expensive RAM (SRAM) is built on triggers, slower but cheaper varieties of RAM - dynamic memory (DRAM) are built on capacitors. In both types of memory information disappears after disconnecting from the power source (for example, current).
By type of access, the memory devices are divided into: - Devices with sequential access (e.g. magnetic tapes) - Devices with random access (RAM) (e.g. RAM) - - Devices with direct access (e.g. 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 tapes); - drum ( magnetic drums); - card (magnetic cards, punch cards, flash cards, etc.) --- printed circuit boards (DRAM cards, cartridges).
According to the physical principle: - perforation (with holes or cuts) –perforated card \u003d\u003d\u003d punched tape \u003d\u003d with magnetic recording \u003d\u003d ferrite cores \u003d\u003d magnetic disks \u003d\u003d Hard magnetic disk \u003d\u003d Flexible magnetic disk \u003d\u003d magnetic tapes \u003d\u003d magnetic cards \u003d optical \u003d\u003d CD \u003d\u003d DVD \u003d\u003d HD-DVD \u003d\u003d Blu-ray Disc
Main characteristics of memory
The most important characteristics of memory are information capacity and speed.
The information capacity of the 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 amount of information stored, it does not include the memory size occupied by service information, for example, backup areas, sync tracks, engineering cylinders, etc. The speed of a memory device is characterized by its temporal characteristics, which include:
Access time (cycle time) we characterize the maximum frequency of access to this memory when reading or writing information. The time of reading (sampling) information is the time interval for accessing the memory from the supply of the read signal to the receipt of the output signal. Information recording time - the time interval from the moment the signal for accessing the memory is supplied until the memory is ready to receive the next portion of information. Important characteristics of the memory are also reliability, device mass, dimensions, power consumption and cost.
30, Microprocessors,their characters, controllers. A microprocessor is a processor (a device that is responsible for performing arithmetic, logical and control operations recorded in machine code), implemented as a single chip or a set of several specialized chips (in contrast to the implementation of the processor in the form of an electrical circuit on a general-purpose basis or in the form of a software model). The first microprocessors appeared in the 1970s and were used in electronic calculators. Soon they began to be embedded in other devices, such as terminals, printers and various automation. Available 8-bit microprocessors with 16-bit addressing allowed the creation of the first household microcomputers in the mid-1970s. Microprocessors are characterized by: 1) a clock frequency that determines the maximum time to complete the switching of elements in a computer;
2) bit depth, i.e. maximum number of simultaneously processed binary bits. 3) architecture. The concept of microprocessor architecture includes a command system and addressing methods, the ability to combine the execution of commands in time, the presence of additional devices as part of the microprocessor, the principles and modes of its operation Microcontroller (born Micro Controller Unit, MCU) - a chip designed to control electronic devices. A typical microcontroller combines the functions of a processor and peripheral devices, contains RAM or ROM. In fact, it is a single-chip computer capable of performing simple tasks. The most important characteristics of a microprocessor are:
31. Microcomputers and their class.Computers of this class are available to many enterprises. Organizations using microcomputers usually do not set up data centers. To service such a computer, they need a small computing laboratory with several people. The number of employees in the computational laboratory necessarily includes programmers, although they are not directly involved in the development of programs. Necessary system programs are usually purchased with a microcomputer, and the development of the necessary applications is ordered to larger computing centers or specialized organizations. You can give the following classification of microcomputers: -- 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) - single-user microcomputers meeting the requirements of accessibility and universality of use, designed for one user and managed by one person - Portable computers are usually needed by business leaders, managers, scientists, journalists who have to work outside the office - at home, at presentations or during travel time.
Main varieties laptop computers:
Laptop. The size is close to a regular portfolio. According to the main characteristics (speed, memory) approximately corresponds to desktop PCs. Now computers of this type are giving way to even smaller ones.
Notebook In size, it is closer to a large format book. Has a weight of about 3 kg. It fits in a diplomatic 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 outages. Even if it receives energy from a conventional power grid, in the event of any malfunction, it instantly switches to battery power.
Palmtop (handheld) - the smallest modern personal computers. Fit in the palm of your hand. The magnetic disks in them are replaced by non-volatile electronic memory. There are no drives on disks - information is exchanged with ordinary computers through communication lines.
Despite the relatively low productivity compared to large computers, micro-computers are also used in large computer centers. There they are entrusted with auxiliary operations, for which it makes no sense to use expensive supercomputers. Such tasks, for example, include the preliminary preparation of data.
Servers are powerful multi-user microcomputers in computer networks dedicated to processing requests from all network stations. Servers are usually referred to as microcomputers. A server is a computer dedicated to processing requests from all stations of a computer network, providing these stations with access to shared system resources (computing power, databases, program libraries, printers, faxes, etc.) and distributing these resources.
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Writing assignment
Exam paper
Issued to the student of the group 35 Romanov Andrey Alekseevich
Profession: “Master in Digital Information Processing”
Subject: “Recording information on removable media”
I. Descriptive part
Introduction
1. Basic terms and concepts
2. Overview of storage media, their advantages and disadvantages, principles of operation, characteristics.
4. Selecting a program for recording information on the media
Conclusion
List of references.
Applications
II. Practical task
1. Create instructions for recording information on the selected removable storage medium
2. Create a work test
3. Create a presentation on the work
The task was given by the master Crack
The assignment was received by student A.A. Romanov
Ministry of Education and Science of the Udmurt Republic
Autonomous vocational educational institution
Udmurt Republic
"College of Radio Electronics and information technologies»
Graduation written qualification work
by profession "Master in Digital Information Processing"
student group number 35
Topic : “Recording information on removable media”
Izhevsk, 2015
Introduction
Storage medium (information carrier) - any material object or medium containing (carrying) information that can sufficiently long time save in its structure the information recorded in / on it. Initially, the amount of information that was 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 3 TB).
The main storage media: hard disk drives (floppy disks), hard disk drives (hard drives), CD, DVD (including Blu-ray, including), flash-memory (flash drives, memory cards).
CD and DVD are firmly entrenched in our lives. It’s hard to imagine where we would store gigabytes of music, movies and photographs if someone hadn’t come up with these round records with a mirror surface.
At the moment, this topic is relevant, because modern man is not able to live without information. But information has this feature - it needs to be stored somewhere. Information storage systems are now quite a lot. It can be stored on magnetic media, 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 result, the reliability of the media. That is why the technology associated with the storage of information so quickly developed.
The purpose of this final qualification written work is:
1. Create instructions for recording information on the selected removable storage medium.
Based on this goal, the following tasks:
1. Make an overview of removable media, identify their advantages and disadvantages
2. Select a program for recording on removable media
Key Terms and Definitions
Information - information perceived by a person or special devices as a reflection of the facts of the material world in the communication process.
Recording Information - This is a way of fixing information on a tangible medium.
Removable media of information - a storage medium intended for its autonomous storage and use independent of the place of recording.
Media Overview
HMD (Flexible Media Magnetic Disks) or Diskette(English Floppy Disk Drive) - a portable storage medium used for multiple data recording and storage, which is a flexible magnetic disk placed in a protective plastic case (a 3.5 ″ disk has a harder case than a 5.25 ″ disk, whereas the disk with a diameter of 8 ″ is enclosed in a very flexible case) covered with a ferromagnetic layer. Floppy disks usually have a write-protect function, through which you can provide access to data only in read mode. Floppy disks were widely distributed from the 1970s to the end of the 1990s, at the beginning of the XXI century giving way to more capacious and convenient CDs and flash drives.
Advantages:
1. Huge recording density with small media sizes.
2. Low power consumption compared to similar high-capacity media.
3. High reliability and stability.
disadvantages:
1. Small recording capacity (in fact, even one song cannot be recorded on a disc).
2. Insecurity of information storage, the floppy disk is demagnetized under the influence of large magnetic fields.
HDD (Hard Disk Drive) or Winchester or Hard Disk(Eng. HDD - Hard Disc Drive) - a storage device based on the principle of magnetic recording. It is the main data storage device in most computers. Combined with a drive, drive and electronics unit and (in personal computers in the vast majority of cases) it is usually installed inside the computer system unit, but there are also external ones that can be connected.
Information is recorded on rigid (aluminum or glass) plates coated with a layer of ferromagnetic material, most often chromium dioxide. In HDD, one or more plates are used on the same axis. The read heads in the operating mode do not touch the surface of the plates due to the interlayer of the incoming air flow generated at the surface during rapid rotation. The distance between the head and the disc is several nanometers (in modern drives about 10 nm), and the absence of mechanical contact ensures a long service life of the device. In the absence of disk rotation, the heads are located at the spindle or outside the disk in a safe area, where their abnormal contact with the surface of the disk is excluded.
The principle of operation of hard drives is similar to that 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 an alternating electric current (during recording) to the head coil, the resulting alternating magnetic field from the head gap acts on the ferromagnet of the disk surface and changes the direction of the domain magnetization vector depending on the magnitude of the signal. When reading, the movement of domains at the head gap leads to a change in the magnetic flux in the magnetic core of the head, which leads to the appearance of an alternating electric signal in the coil due to the effect of electromagnetic induction.
IN lately For reading, a magnetoresistive effect is used and magnetoresistive heads are used in the disks. In them, a change in the magnetic field leads to a change in resistance, depending on the change in the strength of the magnetic field. Such heads can increase the likelihood of reliability of information reading (especially at high information recording densities).
Advantages:
1. Allow to write and read information many times.
2. When you turn off the computer, the information left on the hard drive is saved.
3. A 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.
Disadvantages:
1. The inability to carry it, as it is permanently attached to the system unit.
2. Relatively low speed, especially compared to RAM.
Recording methods
There are currently several recording methods:
· The method of longitudinal recording.
· The perpendicular recording method.
· Thermal magnetic recording method.
Cd or cd(English Compact Disc) - an optical information carrier in the form of a plastic disk with a hole in the center, the process of recording and reading information which is carried out using a laser. A further development of the CDs was DVD (more about them later).
The CD was originally created to store audio recordings in digital view, however, later became widely used as a medium for storing any data in binary form.
CD-ROM (Eng. Compact Disc Read-Only Memory, read: "sit-rum") - a type of CD-ROM with recorded data that is read-only (read-only memory - memory "read-only"). CD-ROM is a modified version of CD-DA (a disk for storing audio recordings) that allows you to store other digital data on it (physically no different from the first, only the format of the recorded data has been changed). Later versions were developed with the ability to write once (CD-R) and re-write (CD-RW) information to disk. A further development of CD-ROMs was DVD-ROMs.
CD-ROM discs - the popular and cheapest means of distribution software, computer games, multimedia and other data. CD-ROM (and later DVD-ROM) has become the main medium for transferring information between computers, displacing the floppy disk from this role (now it is inferior to this role to more promising solid-state media).
The format of recording on a CD-ROM also provides for recording information on a single disc of mixed content - both computer data (files, software, reading is available only on a computer) and audio recordings (played on a regular audio CD player), videos, texts and pictures. Such discs, depending on the order of the data, are called advanced (English Enhanced CD) or Mixed-Mode CD.
Cd-r (Compact Disc-Recordable) is a type of compact disc (CD) developed by Philips and Sony for one-time recording of information. CD-R supports all the features of the "Red Book" standard and plus it allows you to record data.
A regular CD-R is a thin disc made of transparent plastic (polycarbonate) with a thickness of 1.2 mm, a diameter of 120 mm (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 the CD-R can be considered 702MB of data or 79 minutes 59 seconds and 74 frames.
The polycarbonate disk has a spiral path for directing the laser beam when recording and reading information. On the side with the spiral track, 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 coated with a protective photopolymerizable varnish and cured by ultraviolet radiation. And already on this protective layer various inscriptions are applied with paint.
On the CD-R there is always a service track with ATIP servos - Absolute Time In Pregroove - absolute time in the service track. This service track is needed for a tracking system that keeps the laser beam while recording on the track and monitors the recording speed. In addition to the 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 for recording, 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 compact disc) - a type of compact disc (CD), developed in 1997 for re-recording information
CD-RW is the logical development of CD-R, however, unlike it, it allows you to overwrite data many times. This format was introduced in 1997 and was called CD-Erasable (CD-E, Erasable Compact Disc) during development. CD-RW is in many ways similar to CD-R, but its recording layer is made of a special alloy of chalcogenides, which, when heated above the melting temperature, passes from a crystalline state of aggregation to an amorphous one.
DVD(English Digital Versatile (Video) Disc - digital multi-purpose (video) disk) - a storage medium made in the form of a disk having the size of a CD, but with a denser structure of the working surface, which allows you to store and read more information for due to the use of a laser with a shorter wavelength and a lens with a larger numerical aperture.
First drives and dVD players appeared in November 1996 in Japan and in March 1997 in the United States.
In the early 1990s, two standards were developed for high-density optical information 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 standards developers were combined under the leadership of IBM, which did not want a repeat of the format war, as was the case with 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. Amendments and additions to the specifications are made by the DVD Forum organization (formerly called the DVD Consortium), of which 10 founding companies and more than 220 private individuals are members.
The DVD-R (W) recording standard was developed in 1997 by the Japanese company Pioneer and a group of companies that joined it and entered the DVD Forum, as the official specification of recordable (subsequently rewritable) discs.
Based on DVD-R discs DVD-RWs initially had a nuisance related to the incompatibility of old drives with these new discs (the problem was the difference between the optical layer responsible for “storing” information, which had less reflectivity (compared to write-once media and stamped discs) . In the future, this problem was almost completely resolved, although earlier it was because of this that the old DVD-drives could not normally play new rewritable discs.
The created alternative format, called DVD + R and having a different material of the reflective layer and special marking that facilitates head positioning, is the main difference between such “plus” discs and “minus” discs. With this, DVD + RW discs are capable of recording in several steps (over the existing one), as in a conventional video cassette recorder, eliminating the tedious preliminary erasing of all contents (for DVD-RW, you must first completely erase the existing recording).
In addition, when using rewritable “plus” discs, the number of errors decreases, and the correctness of the recording increases, resulting in bad sector You can easily overwrite, rather than erase or burn the entire disc again. 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 capable of now).
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 an installed decoder). DVD movies are compressed using the MPEG-2 algorithm for video and various (often multi-channel) audio formats. The bitrate of compressed video varies from 2000 to 9800 Kbps, it is often variable (VBR). The standard video frame size of the PAL standard is 720 × 576 pixels, and the 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 using the NTSC standard, all DVD movies must contain PCM or AC-3 audio, and all NTSC players must support these formats. Thus, any standard disc can be played on any standard equipment.
Blu-ray Disc, BD (English blue ray - blue ray and disc - disc; spelling blu instead of blue - intentional) - an optical media format used for recording with high density and storing digital data, including high-definition video. The Blu-ray standard was jointly developed by the BDA Consortium. The first prototype of the new media was introduced in October 2000. The modern version is presented at the international 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 got its name from using for recording and reading a short-wave (405 nm) “blue” (technically blue-violet) laser. The letter “e” was deliberately excluded from the word “blue” in order to be able to register a trademark, as the expression “blue ray” is often used and cannot be registered as a trademark.
From the inception of the format in 2006 to the beginning of 2008, Blu-ray has been a serious competitor - an alternative format for HD DVD. Over the course of two years, many of the largest film studios that initially supported HD DVD gradually switched to Blu-ray. Warner Brothers, the latest company to release its products in both formats, abandoned the use of HD DVD in January 2008. On February 19 of that year, Toshiba, the creator of the format, stopped developing in the field of HD DVD.
Flash memory
Flash memory (English flash memory) - a kind of solid-state semiconductor non-volatile rewritable memory (PPPZU).
It can be read as many times as you want (within the data storage period, typically 10–100 years), but you can write to such a memory only a limited number of times (maximum - about a million cycles). Flash memory is common, withstanding about 100 thousand rewriting cycles, much more than a diskette 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 phonesas well as smartphones and communicators. In addition, it is used to store firmware in various devices (routers, PBXs, printers, scanners, modems), various controllers. Also recently, USB flash drives (“flash drive”, USB-drive, USB-drive), which almost supplanted floppy disks and CDs, have become widespread.
At the end of 2008, the main drawback that did not allow devices based on flash memory to drive out hard drives from the market was the high price / volume ratio exceeding this parameter for hard drives 2-3 times. In this regard, the volume of flash drives is not so large, but work is ongoing in these areas. The technological process is becoming cheaper, competition is intensifying. Many companies have already announced the release of SSD-drives with a capacity of 256 GB or more.
At the heart of this type of flash memory is an NOR element (English NOR), because in a transistor with a floating gate, the low voltage at the gate indicates one.
The transistor has two gates: control and floating. The latter is completely isolated and is able to hold electrons up to 10 years. The cell also has a drain and a source. When programming voltage on the control gate, an electric field is created and a tunneling effect occurs. Some of the electrons tunnel through the insulator layer and fall on the floating gate. The charge on the floating gate changes the "width" of the drain-source channel and its conductivity, which is used in reading.
Programming and reading cells vary greatly in power consumption: flash memory devices consume quite a lot of current when writing, while when reading, energy costs are small.
To erase information, a high negative voltage is applied to the control gate, and the electrons from the floating gate pass (tunnel) to the source.
In the NOR architecture, an individual contact must be connected to each transistor, which increases the size of the circuit. This problem is solved using the NAND architecture.
The NAND type is based on an NAND element. The principle of operation is the same, differs from the NOR-type only in the placement of cells and their contacts. As a result, it is no longer necessary to bring an individual contact to each cell, so the size and cost of the NAND chip can be significantly less. Also recording 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, as 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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Educational:
· Promote the formation of a system of knowledge, skills in the field of information and communication technologies used in education.
· Introduce modern digital storage media.
· Consider ways of interaction between the teacher and the subjects of the pedagogical process and representatives of the professional community in the network information environment.
Developing:
· Develop and stimulate student research.
· Develop the ability to assess the benefits, limitations and choice of hardware to solve professional and educational problems.
· Promote the improvement of professional knowledge and skills by using the capabilities of the information environment.
Educational:
· Form a motivation for informational pedagogical activity.
II. Flash memory.
III. Optical discs.
IV. Hard disks.
V. Chips SDRAM.
I. Modern digital storage media.
As a rule, multimedia fragments occupy a large amount of computer memory. And if storing large amounts of information in a computer, in particular, on a Web server, does not cause any special problems, then the transfer a large number Information can take a very long time. For example, the transmission of information of 20 megabytes through a modem operating at a speed of 56 kilobits per second by internetwill be carried out almost an hour. Of course, information can be compressed and thereby reduce the transmission time. However, laser discs, which today are widely distributed and are known as CD-ROMs, are best suited for storing and transporting multimedia training programs.
The most common memory currently:
§ 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 memory include information capacity (bit), power consumption, information storage time, speed.
II. Flash memory (eng. flashmemoryA type of semiconductor technology of electrically reprogrammable memory (EEPROM). Due to its compactness, low cost, mechanical strength, large volume, speed and low power consumption, flash memory is widely used in digital portable devices and storage media.
Specific environmental conditions can catastrophically reduce the shelf life of data. For example, elevated temperatures or radiation (gamma ray and high-energy particles) irradiation.
The erase speed varies from units to hundreds of milliseconds, depending on the size of the erased block. The write speed is tens to hundreds of microseconds.
Typically, the read speed for NOR chips is normalized to tens of nanoseconds. For NAND chips, the read speed is tens of microseconds.
There are two main applications of flash memory: as a mobile storage medium and as a repository of software (“firmware”) for digital devices. Often these two applications are combined in one device.
Flash memory allows you to update the firmware of devices during operation.
