Even more often in the winter storage it is necessary to obtain information, as it does not change in the process of exploitation of the annex. Tse such information like programs in microcontrollers, pochatkovy zavantazhuvachi (BIOS) in computers, tables of performance of digital filters in signal processors, DDC and DUC, tables of sine and cosine DDS in NCO. In practice, it is not necessary to generate information overnight, because the simplest attachments for storing the continuous information (ROM) can be used on multiplexers. Once in the translation literature, the memory is stored as ROM (read only memory - memory is available only for reading). A diagram of such a permanent memory (ROM) is shown on little 3.1.

Malunok 3.1. The scheme of permanent memory (ROM), prompted on the multiplexer.

In this scheme, a persistent memory is prompted for a long time on single-bit alternating paths. Zapam'yatovuvannya of a particular bit in a single-bit midway vyroblyatsya zapayuvannya drot to dzherela vivlennya (record odinitsі) or sealed darts to the body (write zero). On the principles of diagrams, such prist_y to mean yak is shown on little 3.2.

Malunok 3.2. The designation of permanent memory on the principles of diagrams.

In order to make sure that the size of the memory of the memory of the ROM and the microcircuit can be increased parallel The scheme of parallel storage of single-bit ROMs is aimed at little 3.3.

Malunok 3.3 Scheme of multi-bit ROM (ROM).

In real ROMs, information recording is carried out for an additional operation of the microcircuit - metalization. Metallization is carried out behind an additional mask, so this ROM is called mask ROM. Another example of real microcircuits from the simplified model, induced by the target is the price of the multiplexer and demultiplexer. This solution allows converting a single memory structure into a two-world one, at the same time, at the same time, the speed of processing the decoder circuit, which is necessary for the robotic ROM circuit. The situation is illustrated by an offensive little guy:

Malunok 3.4. Scheme of masked permanent memory (ROM).

The masochny ROM is displayed on the principles of diagrams as shown on the little 3.5. The addresses of the middle memory in the whole microcircuit are applied to the templates A0 ... A9. The microcircuit is vibrated with a CS signal. For an additional signal, it is possible to increase the volume of the ROM (the butt of the switch to the CS signal is triggered before the hour of RAM negotiation). The microcircuit is read by the RD signal.

Malunok 3.5. Intelligent graphical designation of mask ROM (ROM) based on the principles of diagrams.

The program of the masked ROM is rocked at the factory, which is even more difficult for other and medium-sized devices, not even thinking about the stages of the development of an extension. Naturally, for a large-scale production of masochka ROMs є the most expensive type of ROM, and it becomes widespread in a given hour. For other and mid-range radio devices, microcircuits have been broken up, which can be programmed in special annexes - programmers. In the cich ROM, the data of the providers in the memory matrix is ​​replaced by fusible links, prepared from polycrystalline silicon. When the ROM is virobnited, all jumpers are available, which are equivalent to recording in the middle of the memory of the ROM of logical units. In the process of the programmed ROM, the harvesting instructions will be sent to the microcircuits. At the same time, if the output of the ROM is fed with liveness (a logical one), then the current will not flow through the jumper and the jumper will not be overpowered. As soon as on the output of the ROM there is a low level of pressure (bring it to the body), then through the memory matrix there will be against the strum, which is a vipar, if you read the information from the future memory of the future.

Such microcircuits are called programmed ROM (EPROM) or PROM is displayed on the principles of diagrams as shown in Figure 3.6. Yak butt PPZU can be named microcircuits 155PE3, 556RT4, 556RT8 and іnshі.

Malunok 3.6. Intelligently graphical designation of programmed permanent memory (PROM) based on the principles of diagrams.

The programmed PZP has evolved even more manually in case of variable-serial and medium-serial production. However, when developing radioelectronic attachments, it is often necessary to write a program in the ROM. At the same time, it is unfortunate that the PROM is vikoristovuvati again, that time the ROM is written down with the grave or the industrial program to be brought to the wikidat, which naturally increases the part of the distribution of the apparatus. There is one more type of ROM for usunennya ts'ogo shortcomings of the breakdowns, which can be erased and programmed anew.

ROM with ultraviolet erasures will be based on a memory matrix stimulated on memory elements, internal devices which are aimed at the offensive little one:

Malunok 3.7. Zapam'yatovuє in the middle of the ROM with ultraviolet and electric erasure.

The middle is a MOS transistor, in which the gate is exposed to polycrystalline silicon. Then, in the process of preparing a microcircuit, the shutter is oxidized as a result of the release of silicon oxide - a dielectric with excellent insoluble power. In the description, the ROM is erased when it is turned on, the charge in the floating gate is not conductive, and the transistor strum is not carried out. When the ROM is programmed, the other shutter, which is located above the floating shutter, is supplied with a spout and a charge is induced into the floating shutter for the tunnel effect opening. When the zenyattya program the induction springs, the charge is lost on the floating gate, and, therefore, the transistor is left in the wire. The charge on the floating shutter can take dozens of rockets.

The block diagram of the described permanent memory does not appear from the previously described mask ROM. One reason - the replacement of the floating bridge is described in the middle of the river. This type of ROM is called reprogrammed with external attachments, which can be stored in memory (EPROM) or EPROM. At the RPZU, the deletion of the previously recorded information is effective for ultraviolet vippromise. In order for the light to pass smoothly up to the conductive crystal, the microcircuit ROM is inserted into the microcircuit case at the end of the quartz slope.

When the microcircuit of the RPZU is optimized, the insulating power of silicon oxide is consumed, the accumulation of the charge from the floating shutter is charged in the volume of the conductor, and the transistor is transferred to the shutter mill. An hour of erasing the microcircuit of the RPZU lasts between 10 and 30 chilines.

The number of cycles I will write - the erasing of EPROM microcircuits is in the range from 10 to 100 times, when the EPROM microcircuit goes out of order. The price is tied with a ruynivny injection of ultraviolet viprominuvannya on silicon oxide. Yak butt of microcircuits EPROM can be called microcircuit 573 of the Russian version, microcircuit of the 27cXXX series of the foreign version. RPZUs are most often used with BIOS programs for universal computers. The RPZU is displayed on the principles of diagrams yak shown on little 3.8.

Malunok 3.8. Intelligent graphical designation of EPROM (EPROM) based on the principles of diagrams.

So, as the case with a quartz end is narrower than the road, as well as a small number of cycles I will write down - the erasure led to the idea of ​​erasing information from the RPZU in an electric way. On the whole path of development, a lot of difficult things, which are practically revised up to the present hour. Infected to reach widespread microcircuits with electrical information erasures. As a memory in them, they are also vikoristovuyutsya midway and in RPZU, ale the stench is erased by the electrical potential, so a number of cycles I will write down - erasing for cich microcircuits reaches 1,000,000 times. The hour of erasing the memory in such ROMs is reduced to 10 ms. The control circuit for electrically erasing programmed ROMs was collapsible, so there were two directions for the development of microcircuits:

1. EEPROM (EEPROM) - to erase programs of a permanent memory

Electrically prani EPROM (EEPROM) is more expensive and less expensive, but it also allows you to rewrite the skin of the memory okremo. As a result of microcircuits, I write as many cycles as possible - erasure. The area of ​​storage of electrically erased ROMs is a collection of donations, which are not guilty of being erased during activation. Prior to such microcircuits, microcircuits 573РР3, 558РР3 and foreign microcircuits of EEPROM series 28cXX are known. Electrically prani ROMs are poznachayutsya on the principles of diagrams as shown on little 3.9.

Malyunok 9. Intelligently graphic designation is electrically changed over the post memory (EEPROM) on the principles of diagrams.

The remaining hour saw the tendency to change the dimensions of the ESPROM for the reduction of the number of new microcircuits. For a given address and data are transmitted to the microcircuit and from the microcircuit through the last port. At the same time, there are two types of last ports - SPI port and I2C port (microcircuits 93cXX and 24cXX are available). Foreign series 24cXX is a version of the latest series of microcircuits 558PPX.

FLASH - ROM is generated from the ESPROM, so that the erasure is not carried out on the skin layer, but on all microcircuits in the whole block of the memory matrix of the microcircuit, as it was done in the EPZU.

Malunok 3.10. Mind-graphical designation of FLASH memory based on the principles of diagrams.

When the memory is zoomed to the permanent memory of the attachment, it is necessary to display the address in the middle of the memory on the bus address, and then to complete the operation of reading from the microcircuit. Tsya Timchasova Diagram is given on little 3.11.

Malunok 3.11. Timing diagrams of signals in reading information from ROM.

On little 3.11, arrows show the last, in which the signals are formulated. On the whole little one RD - the signal of reading, A - signals to the vibrator of the address and the middle vibrating room ROM.

4. Enter the folding operation in a pre-order code, presenting the location of the warehouses in a two-way view:

1) + 45 2) - 45

- 20 + 20

Decision:

1) x 1 = 45 = 0.101101 ін

x 2 = - 20 = 1.010100 pr = 1.101011 arr = 1.101100 add

+ 1,101100

as follows: 0.011001 in = 25 10

2) x 1 = - 45 = 1.101101 ін

x 2 = 20 = 0.010100 in

+ 0,010100

as follows: 1.100111 add = 1.011000 arr = 1.011001 pr = - 25 10

Food number 5.

Vykonayte navdannya:

1) write down the logical function in the SNDF;

2) minimize the logical function behind the additional Karnot cards;

Personal computers can be used for the following:

microprocessor memory;

main memory;

restrov cache-memory;

call memory.

Microprocessor memory is visible. The main memory is designated for the collection and operational exchange of information from the outbuildings of the computer. Memory functions:

reception of information from the outbuildings;

memorizing information;

Providing information behind the power supply in the attachment of the machine.

The main memory is to take revenge on two kinds of memory annexes:

ROM - permanently zapam'yatovoy prist_y;

RAM - operatively zapamyatovoy pristіy.

ROM is designated for the collection of post-proprietary software and pre-existing information. Data in ROM should be entered when ready. Information that can be stored in ROM can only be zchituvati, but not zm_nyuvati.

The ROM has:

program for controlling the processor's robot;

program for launching a computer;

programs for testing attachments, changing the correctness of the robotic blocks when the computer is turned on for the skin;

control programs for displays, keyboard, printer, memory;

Information about those on the disk that the operating system is located.

ROM is an energy-independent memory, when the information is turned on, it will be stored in a new way.

OZP indications for operational recording, retrieval and reading of information (programs and data), without the need to take a part in the information-computational process, as well as being displayed by a computer during the current period of an hour.

Headend perevagami operativnoї pam'yatі Je її Visoka shvidkodіya i mozhlivіst zvertannya to kozhnoї komіrki pam'yatі okremo (direct address to access pam'yatі). All memory units are collected in groups of 8 bytes (1 byte), such a group has an address, for which it is possible to turn around.

RAM є energy storage memory, when enabled, information will be erased.

For modern computers, the memory size should be 8-128 MB. Obsyag memory - the characteristics of the computer are important, it is infused into the speed of the robot and the efficiency of the program.

Likewise, ROM and RAM on the system board є і is not available CMOS memory, it is permanently harvested from its battery. They have the parameters of the configuration of the computer, which are reconfigured when the skin system is switched off. Tse semi-permanent memory. To change the parameters of the computer's configuration in the BIOS, there is a program for setting up the computer's configuration - SETUP.

For quicker access to the operational memory, a special overhead cache memory is created, as a microprocessor and an operational memory, copies of the most frequent copies are taken. The register cash memory is not available for the koristuvach.

At the cache memory, data is taken, as a microprocessor will be able to pick up and be victorious in the best tactics of his robot. A quick access to the tsikh danih allows you to speed up the hour of visiting the Chergov teams with programs.

Microprocessors, repairing from MP 80486, can change their cache memory. Microprocessors Pentium and Rentium Pro can cache okremos for tributes and okremos for teams. For all microprocessors, there can be additional cache memory, which can be placed on the motherboard in the microprocessor's position, in which you can reach the decile MBytes. The name of the memory is used for the newest attachments of the computer and for the pre-prepared collection of information, as it may be known for the new building. In the morning, all programs of the computer are saved at the last memory.

The annexes of the memory of the past are the outcrops, and the memory of the memory is even more important. You can classify it by the type of nose, by the type of construction, by the principle of recording and reading information, by the method of access, etc.

Naybіlsh wider new outbuildings, scho to remember є:

accumulate on hard magnetic disks (HDD);

accumulate on dull magnetic disks (NGMD);

accumulate on optical disks (CD-ROM).

In the past, in the capacity of annexes to the last memory of a personal computer, to be attached to the memory of a cassette magnetic strip - streamers.

Accumulate on disks - tse attachments for reading and record from magnetic or optical carriers. Appointment of the number of accumulations is the acquisition of great information reports, the recording and delivery of information, so that you can use the power supply in the operational setting.

HDD and NGMD are developed only constructively, by means of information reports, so that they can take a joke for an hour, and write down that information.

As the memory of the middle of the magnetic disks, the magnetic materials are victorious with special authorities, so they allow the fixation of two magnetic camps - two straight lines of magnetization. For the skin, it is placed at the display of the numbers 0 and 1. Information on the magnetic disks is recorded and read by the magnetic heads of the concentric bridges - tracks. Number of disk drives and information It is possible to lay down according to the type of disk, the design of the storage device, the quality of the magnetic heads and the magnetic coil. The leather door is split into a sector. One sector is allocated 512 bytes of data. The exchange of data between them is accumulated on a magnetic disk and the operative memory will last by as many sectors as possible. For a hard magnetic disk, one must also be able to understand the cylinder - the doors, which are located at the same point towards the center of the disk.

Discs can be accessed by direct access to machine information carriers. This means that the computer can be turned up to the road, to repair the file from the shukanoy information, or where it is necessary to write down new information, without the average, if the head is not known to write down the reading.

All disks - magnetic and optical - are characterized by their own diameter (form factor). Three dull magnetic disks of the most widened were filled with disks with a diameter of 3.5 (89 mm). The number of disks becomes 1.2 і 1.44 MB.

Nakopichuvachi on hard magnetic disks was called "Winchester". Tsei term vinik from the slang name the first model of the hard disk, there are 30 paths of 30 sectors of the skin, which is vipadkovo zbigloya with the caliber of Mislivska rushnitsa "Winchester". The memory of a hard disk drive is stored in MB and GB.

In an hour, new storage on magnetic disks - ZIP-disk - portable attachments with 230-280 MB memory appeared.

In the rest of the rockets of the most widespread distribution, they started saving up on optical disks (CD-ROM). Breeders of small sizes, great strength and hopefulness and accumulation become more and more popular. The number of accumulators on optical disks is 640 MB and more.

Optical discs can be used for non-rewritable laser-optical discs, rewriting of laser-optical discs and rewriting of magneto-optical discs. Non-rewritable disks are supplied by virobnik companies with information already recorded on them. Recording information on them can only be done in laboratory minds, the pose of a computer.

Apart from its main characteristics - informational capacity, disk accumulators are characterized by two hour indicators:

hour access;

shvidk_styu reads asp_l roztashovanih bytes.

Basic provisions.

Memory in the microprocessor system of the vicon with the function of the donation. Developed types of memory are used for the collection of different types of donations. More details will be shown below.

Information in memory is stored in the middle, the number of lines of various road numbers of lines in the bus of the processor. Name it in multiples of eight. Tse is tied with tim, shho byte є Eight-row one vimir. To that, the memory will most often be displayed in bytes, regardless of the size of the memory commander.

It is permissible for a number of intermediate memory numbers to start in the number of address lines of the bus address yak 2N, de N - number of address lines on the bus.

There are also large amounts of memory: cylobyte - 210 = 1024 bytes (used as KB), megabytes - 220 = 1,048,576 bytes (used as MB), gigabytes - 230 bytes (used as GB - 240, terabytes TB). For example, if the memory is 65,536, the skin is 16-bit, then it seems that the memory is 128 KB in size. Sukupn_st elements of the memory is called zzvivay the spaciousness of the memory.

To connect the memory module to the system backbone, there are blocks of output, which include an address decoder (selector), a circuit for processing signals in the backbone and data buffers (Fig. 8.1). To connect the memory module to the system backbone, there are blocks of data obtained, which include an address decoder (selector), a circuit for processing signals in the backbone and data buffers (Fig. 2.18).

Call in the warehouse of the system a number of memory modules, leather goods in your area for the vastness of memory. The address selector yakraz and viznachaє, as the address area to the vastness of memory is introduced to this memory module. The control circuit of the viroble at the required moment signals the permission of the robotic memory (CS - Chip Select) and signals the permission to write to the memory (WR - Write-Read). Data buffers transfer data from the memory to the main or from the main to the memory. In the vast memory of the microprocessor system, you can see a number of special areas, such as special functions.

Classification of memory modules.

The classification of memory is necessary for a more clear understanding of the one for whom that memory will be victorious.

First for everything, memory lasts for two main groups: permanent memory lock (ROM) and operational adjustment (RAM).

Permanent zapam'yatovoy prist_y (ROM).

Let us permanently memorize the annexes to name the independent memory, so that the memory does not lie in the presence of a force of living on the annex. In this kind of information, it can take a trivial hour without plugging in to get live.

The Danish type of memory is used for obtaining information, as it is not guilty but for the loss of livelihood at the outbuilding. Until such tribute, it is possible to introduce a program for a microcontroller, data about setting up a set of programs, and files. Before files can be placed graphic images, data, knowledge from sensors, etc.

Ісnu without lіch rіznih realizatsіy ROM. Among microcontrollers, the most popular are two technologies. Tse - EEPROM (Electronically Erasable Programmable ROM) and flash (Flash Erase EEPROM).

EEPROM was broken in 1979 by Intel. The memory can be reprogrammed when the processor is connected to the standard bus. Moreover, the erasure of the memory of the memory is automatically displayed when new tributes are recorded in the new tribute. Including In a whole type of memory, there is a possibility of changing information in one commerce without breaking down the middle.

Flash memory є with a given EEPROM connector. They have a simple type of EEPROM transistor. The first organization of access to the middle of the memory. As a result, access to a short period of time becomes more efficient. The only erasure in the flash memory is carried out only for the singing block of tributes, or for the whole microcircuit as a whole. To erase one element in it is unwise. And so, as a record in a single type of microcircuit (for the type of memory NAND) is carried out by element "I" of the flow line in the middle with the data required to be recorded, then the actual data will be recorded in the class of only one in the same way, as in some of the week ... You can install one in the middle only by the erasing function. Any kind of recording of tribute is not possible. Otzhe, in order to write down the data in one memory room, you need to copy the entire block to the side, which will be erased, erase it. At the memory of remembering the meaning of the required alternation, and also of changes, the block of writing back.

It is possible to back up the robot with a few seconds of data due to the need for skin copying and the use of a block of data. Ale of the robot is right there with the block in the EEPROM.

Including Flash has a sense of obtaining information, as it will change quickly (or not). And in the EEPROM it is possible to record the adjustment of programs, which are guilty of being careful not to write the add-on from the harchuvannya.

Flash memory of two types - NOR and NAND. NOR (Not OR) Fast and reliable access to the middle of the memory and the ability to write byte. NAND (Not AND) allows you to record and erase the tribute, but it will take more than an hour to access the tribute in the case of NOR.

From the peculiarities of the memory structures, NAND invite you to pick up information, read it in a stream, such as video, music, etc. NOR zh vikoristovutsya for zberіgannya programs, zabdyaki vysokіy shvidkostі readings of a dovіnogo byte danih.

The ROM is obviously low-speed and cannot be used for obtaining information, until a quick access is required, such as a quick access.

The memory of the cob start programs is always visible on the ROM. In the center of the region, the processor repairs the robot to turn on the live and send it off for the additional RESET signal. If the microcontroller has a decal type of ROM, it often starts the program with a clear vibration from them. For a wide variety of names, there is a number of nizhok, a combination of signals on any identifying that is in the ROM.

NAND addressing.

For the butt of the robot from the ROM, it is possible to organize the memory and turn it up to it on the butt of the NAND memory microcircuit.

The structure of the NAND memory is shown in Figure 8.2.

The memory in the microcircuit is divided into blocks, which in its own way can be distributed to the side, which is stored in bytes. Including For a new addressing of a memory byte, it is necessary to know the block number, the page number and the byte address itself in the central part.

The headquarters of the memory in the whole range of transport links to the number of sides in the block and to the number of blocks in the microcircuit of the memory. As far as we have, as shown in Figure 8.2, the microcircuit is stored for 2000 blocks, so there are 128 sides of leather. In the side there are 8192 bytes of memory. As a result, we will recognize: 8192 * 128 * 2000 = 2 GB of memory. Name the size of the memory in bits. So that the size of this microcircuit becomes 16GB, which will be indicated in its documentation.

Apparently, for the removal of one byte of information on the R / W output, when it is indicated for reading a record, a signal will be set to indicate that it will be read. The command is written to read the byte danikh. Then the package is shaped like it is shown in Fig 8.3.

At the same packet A13-A0 - the whole byte address in the side, A20-A14 - the price of the side, A32-A21 - the whole number of the block.

In the case of the power supply, the microcircuit is responsible for the type of byte power supply. At the same time, if it is necessary to vvazat a few bytes aspil, then it is easy to finish the prodovzhuvati zchituvati dania without updating the address. The microcircuit automatically changes the addresses to one unit in case of skin reading. That is, when the microcircuit is victorious, it is visible to read the data all at once (in our application, 8192 bytes each).

Statti before reading:

ROM - permanently stored memory

tipi rom

ROM - it will be encrypted as a permanent memory lock, so that I will not be able to obtain information on any physical basis. For the method of obtaining information, the ROM can be divided into three types:

1. ROM based on the magnetic principle of information collection.

The principle of robotic adaptations of data on changes in the direction of the magnetization vector of feromagnetics in the form of a variable magnetic field in response to the significant bits of the recorded information.

Pheromagnet is a speech that is good at temperatures below the lower threshold (points of Curi) and the volodymy of magnetization when the magnetic field is outside.

The reading of the recorded tribute in such annexes is based on the effect of electromagnetism or magnetoresistive effect. The whole principle is realized in the annexes with a rugged nose at the viglyadi of the disk or lines.

Electromagnetic induction is called the effect of an electric stream in a closed circuit when the magnetic flow changes to pass through a new one.

Magneto-resistive effect of setting on the change of an electric support of a solid conductor under the influence of a magnetic field.

The main reason for this type is the great volume of information and the low part of one information, which can be taken care of. The main drawback is the appearance of crumbling parts, large dimensions, low reliability and sensitivity to the latest injections (vibrations, blows, shifting, etc.)

2. ROM based on the optical principle of information collection.

The principle of robotic attachments of attitudes on the basis of changes in the optical power of the nose is, for example, for the change in the level of vision or performance. The application of the ROM, based on the optical principle of obtaining information, can serve as CD -, DVD -, BluRay - discs.

The main reason for the transfer of this type of ROM is the low parity of the nose, the speed of transport and the ability to circulate. Shortcomings - low readability / recording, few re-recordings, the need for a reading attachment.

3. ROM based on the electrical principle of information collection.

The principle of robotic attachments of storage at the threshold effects in the conductive structures - the ability to secure and reestablish the manifestation of the charge in the isolated area.

The whole principle is vikorystovutsya in solid memory - memory, but not vikorystannya crumbling parts for reading / writing tributes. Flash memory can be used by the ROM application based on the electrical principle of information storage.

The main reason for this type of ROM is the ability to read / write, compactness, reliability, economy. Incomplete - the number of rewrites is interrupted.

For a given moment, there is something about being on the stage of the outlet and the "exotic" type of permanent memory, such as:

Magnetic-optical memory- memory, which is on the same power of optical and magnetic accumulations. Recording on such a disk will go through a path of heating with a laser to a temperature of about 200 ° C. Rosigrita also consumes a magnetic charge. It is possible to cool down in the middle, which would mean that there is a logical zero in the middle of the records, or recharge it with a magnetic head, which would mean that a logical one is written in the middle.

When cooling the magnetic charge in the middle of the change is not possible. Zchituvannya vyroblyaєa laser exchange of lower intensity. As soon as a magnetic charge is placed in the middle, then the laser line will be polarized, and when it is read, the laser will be polarized. For the "fixing" of the magnetic charge when the magnetic-optical is cooled, there is a high degree of efficiency in obtaining information and, in theory, it is possible to write more information on the basis of the memory principle. However, to replace the "hard" discs, the stench cannot be recorded through the low speed of recording, because of the need for a high heat in the middle.

The wide expansion of the magnetic-optical memory didn’t negate and grow even worse.

molecular memory- the memory is based on the technology of atomic tunneling microscopy, which allows for the addition of atoms to the molecule, the appearance of which can be read by special sensitive heads. This technology was presented in the middle of 1999 by the company Nanochip, and theoretically allowed the packing capacity to reach close to 40 Gb / cm 2, but in dozens of times it changed the sharpness of the "hard" discs, but the technologist said that the dose was too low. about practical vikorystanny molecular memory in an accessible to the eye maybutny.

holographic memory- see from the most extended types of permanent memory, but to write down one or two surface balls, you can write down the data on "everything" with a lot of memory for the help of other children Most of the time, this type of memory is stored in ROM on the basis of optical information collection, and even not a novelty is optical discs from a decalcom with information balls.

I’m aware of the fact that it’s still an exotic type of permanent memory, but if it stinks in laboratory minds, balancing on the edge of science fiction, then I won’t talk about them, wait a minute.

Permanent memory lock (ROM)- memory, designated for the collection of unimportant information (programs, constants, table functions). In the process of revision, the ROM is only allowed to read the information. Yak characteristic butt zasosuvannya ROM can be inserted into BIOS ROMs, vikoristovuvanі in PC for zberіgannya BIOS (Basic Input Output System - the basic system of introduction-vivedennya).

In the zagalny vypadku have accumulated ROM r+ 1 razryad_ in skin, zvychay is a system with EPZU horizontal (address) і r+ 1 vertical (razryadnyh) guides, which at the points of cross-flow can be connected with a link (Fig. 1.46). Elementi zyazku (EU) - all fuse links abo p-n- go to. Evidence of the element of the sound j-m horizontal i i-m vertical guides means that in i-m rows of the middle of the memory number j one is written down, the visibility of the EU means, but zero is written here. Writing a word to the number j ROM is carried out by proper placement of elements in the connection between the distribution providers and the address wire number j... Reading words from the number j ROM is displayed like this.

Small. 1.46. Nakopichuvach ROM to the memory of EPZU sliv, r+ 1 section in leather

address code A = j deciphered, і to the horizontal provider number j nakuchichuvacha to be served with vid dzherela zhivennya. Tі from the distribution providers, as we will pick up the address provider with elements of the call, to appear in the opposite direction U 1 ryvnya odinitsi, sieve razryadny providers zalishayutsya pіd prugoyu U 0 rivnya zero. Signal rate U 0 і U 1 on distribution providers and approved in place of the YAP number j, And the very word for the address A.

In the given hour, the ROM will be from the BIOS ROM, for those who are vicarious will be navprovidnikov EU. BIS ROM is accepted for three classes:

- mask (MPZU);

- programmed (EPROM);

- reprogrammable (EPROM).

mask ROM(ROM - as Read Only Memory) - ROM, information to be written from a photomask in the process of growing the crystal. For example, BIS ROM 555RE4 of 2 kbytes is a symbol generator behind the YAKI-8 code. The excellence of the masochka ROM is superior, and not so much - the low technology.

programmed ROM(PROM - Programmable ROM) - ROM, information in which to register as a clerk for additional special attachments - programmers. Dany BIS is available with a new set of EU at all points of the address and distribution providers. The process of advancing the technology of such BIS, and hence, the mass of the virobability and the storage. The recording (program) of information in the EPROM is carried out by the clerk behind the month of the day. To fight with the speed of vipaluvannya of the elements of the sound in quiet points, in which the fault was recorded zeros. Apparently, for example, on TTLSh-BIS EPZU 556RT5 with 0.5 kbyte memory. The reliability of the BIS PRZU is lower than that of the mask BIS. Before the programs, it is necessary to test the EU's presence.

At MPZU і EPZU it is unpleasant to change it in the place of YP. reprogrammable ROM(RPZU) allow bagatorazovuyu change to get information in them. In fact, RPZU - tse RAM, for some t RFP >> t NS. Replaced with the RPZU. EPROMs are issued with electrical (EEPROM) and ultraviolet (UVEPROM) erasures of information. For example, BIS RPZU with electrical erasures KM1609RR2A of 8 kbytes can be reprogrammed at least 104 times; BIS RPZU with ultraviolet erasures K573RF4A with an 8 kbyte memory allowance not less than 25 rewriting cycles, the information from the switched on mill is not less than 25,000 hours, and in the installed one - not less than 100,000 years.

The main feature of the RPZU is the replacement of the ROM in the distribution systems and the improvement of the software security, microprocessor systems and others, if it takes an hour every hour to make changes in the programs.

The ROM robot can look at it unambiguously N-based address code A v n The size code is read from a word, tobto ROM є we re-convert the code (by a digital automaton without memory).

In fig. 1.47 shows a clearer picture of the ROM on the diagrams.

Small. 1.47. Smarter than the image ROM

The functional diagram of the ROM is shown in Fig. 1.48.

Small. 1.48. Functional diagram of ROM

For the terminology adopted in the middle of the fahivts, the input code is called the address, 2 n vertical tires - numerical lines, m vikhodiv - by the discharges of the cherished word. When it is appropriate to enter the ROM, be it a double code, one of the numeric lines will be vibrated. At the same time at the outlets of quiet elements of the ABO, the sound of the given numerical line does not appear to be 1. It means that in this order of the reverse word (abo the numerical lines) it is written 1. At the outlets of the quiet lines, the sounds On the other hand, the numerical line of the vipalena, to lose zero. The program law can be and inverted.

In such a rank, ROM is a functional university for n inputs i m by vikhody, like zberigay 2 n m razryadnyh sliv, as with the robot, the digital attachment does not change. When submitting to the input ROM, the address appears on the output, the word appears. With a logical projection of a permanent memory, it looks like a memory with a fixed set of words, or like a code rewriting.

In the diagrams (div. Fig. 1.47) ROM is designated as ROM. Permanently memorize an attachment, call the input according to the permission of E. If you are active on the input of the E ROM, you will see its function. When there is permission, the microcircuits are inactive. As long as you allow inputs to any of the inputs, so the microcircuit will follow the video signal at the inputs. In the ROM, the E signal is often called the reading of the CHT (read), the vibration of the microcircuit VM, the vibration of the VK crystal (chip select - CS).

Microcircuits of ROM are attached for expansion. To increase the number of circuits in the saving slots, turn on all the inputs of the microcircuits in parallel (Fig. 1.49, a), And from the increase in the total number of inputs, we know the type of word that is different in size.

For an increase in the number of saving words themselves (Fig. 1.49, b) Addresses and input microcircuits turn on in parallel and look at how youngsters the new, expanded address is. Before the older discharges of the new address come to the decoder, one of the microcircuits is selected at the E inputs. With a small number of microcircuits, the deciphering of the older series can be done at the conjunction by allowing the inputs of the ROMs themselves. Leave the same distributions with an increase in the number of saved cases of guilt, depending on the additional function of the ABO. There is no need for special ABO elements, as long as you go to the microcircuits of the VICONANI ROM, either for the circuit of the open collector for connection by the mounting ABO method, for the buffer circuit with three camps, but for the tolerance of the middling process.

Enter the microcircuits of the ROM, change it to inversion, often inversion to the memory, but also to the input of E. CU (for example, automation attachments), expanding ROMs will not give rise to the principles of problems.

Small. 1.49. Increase in the number of slots in saving slots with parallel connected inputs to microcircuits and an increase in the number of saved slots when parallely addressable inputs in microcircuits are enabled