Random access memory, or RAM - this is one of the main elements of a computer. "Operational" memory because it is very fast acting and allows the processor with little or no noticeable wait to read the information from the memory. Contained in the RAM data is stored and accessed only when the computer is turned on. When you turn off the computer contents erased from memory, because before you turn off all Computer data should be preserved. The amount of RAM (by the way, it is called RAM - random access memory) depends on the number of tasks that can simultaneously make Comp.
Operational pamyatOperativnaya memory - a work area for the CPU computer. In it during store programs and data. Memory is often regarded as temporary storage, because the data and the program in it saved up only when the computer or before pressing the reset button (reset). Before turning off or by pressing the reset button, all data subject to change at work, you need to save to the memory, which can store information permanently (usually a hard disk). With the new power-stored information can then be loaded into memory.
Device memory storage devices are sometimes called random access. This means that access to the data stored in memory, does not depend on their order in it. When they say the memory companies, traditionally involve memory, especially the memory chips or modules, which contain the active programs and data used by the processor.
Within a few years the definition of RAM (Random Access Memory) reincarnated common abbreviation of the term, which means the main working area of memory chips produced DRAM (Dynamic RAM - DRAM) and used by the processor to run programs. One of the properties of circuits DRAM (and, therefore, memory in general) is a dynamic data storage, which means, first, the possibility of multiple entries of information in memory, and, secondly, the need to keep the data (ie, in fact, their dubbing) approximately every 15 ms (milliseconds). There is also the so-called static RAM (Static RAM - SRAM), which does not require constant updating. It should be noted that the data is preserved in the memory only when the power is on.
By computer memory RAM traditionally assumed (RAM), ie physical memory of the system, which consists of chips or memory used by the processor to store the key, running at the current time code and data. With this, the term "data warehouse" refers not to the memory, to devices such as hard drives and tape drives (which, however, can be used as a type of RAM, dubbed virtual memory).
The term "memory" often means not only the chips that make up the memory device in the system, but also includes such thing as a logical mapping and placement. Logical mapping - a method of the address memory chips actually installed. Accommodation - this location is disk imaging (data and instruction) of a particular species to specific addresses memory.
While the program in memory saved up its data. Chip memory (RAM) is sometimes called volatile memory: after turning off the computer data stored in them will be lost if not previously saved to disk or other external memory device. To avoid this, some applications automatically make backup copies of the data.
Files computer program when it starts, it loads into RAM, which saved up while working with this program. The processor executes the software implemented commands in memory, and stores the results. Memory stores the codes which the keys are working with a text editor, but also the value of mathematical operations. When you click Save (Save) the contents of memory is saved as a file on your hard drive.
The physical memory in the system is a set of chips or modules containing the chips, which are traditionally connected to the system board. These chips or modules can have different properties and in order to function correctly, must be compatible with the system, which are established.
In advanced computers used memory devices 3 main types:
ROM (Read Only Memory). Only Memory - ROM is not able to do the operation data recording.
DRAM (Dynamic Random Access Memory). Dynamic random access memory with an arbitrary order of the sample.
SRAM (Static RAM). Static RAM.
ROM memory type
The memory type ROM (Read Only Memory), or ROM (read only memory device), the data can only be stored, they can not change. It is precisely because this memory is only used to read the data. ROM is also often referred to as non-volatile memory, so that any data written to it is stored at power off. Therefore, the ROM put the command to start the PC, that is, software that boots the system.
ROM and RAM - not opposites. In fact, ROM is part of the system RAM. In other words, the address space is reserved for memory ROM. This is needed to store the software that allows you to load the operating system.
The basic code is contained in the BIOS ROM chip on the motherboard, but the boards are adapters have similar chips. They contain auxiliary BIOS routines and drivers that are needed for a particular card, especially for those boards that need to be activated at an early stage startup, for example video card. Boards that do not need drivers at an early stage startup, usually do not have ROM, because their drivers can be loaded from the hard drive later - in the boot process.
Currently, most systems use one of the forms of Flash-memory called electrically erasable programmable memory unchanged (Electrically Erasable Programmable Readonly Memory - EEPROM). Flash-memory is a truly non-volatile and rewritable, it allows users to easily modify the ROM, the firmware of motherboards and other components (such as video cards, board SCSI, peripherals, etc.).
DRAM memory type
Dynamic random access memory (Dynamic RAM - DRAM) used in most of the advanced systems RAM PC. The main advantage of this type of memory is that it is very densely packed cells, ie a small chip can pack a lot of bits, and thus on their basis can build mass storage.
Memory cell in the chip DRAM - are tiny capacitors that hold a charge. So (the presence or absence of charges) and coded bits. The difficulties associated with this type of memory, due to the fact that it is dynamic, that is, must be continuously regenerated, because otherwise the electrical charges in the capacitors memory will "drain" and the data will be lost. Recovery occurs when the memory controller, the system takes a little break, and calls on all the lines of data in memory chips. Most systems have a memory controller (usually built into the motherboard chip set), which is set to an industry standard frequency of recovery, the same, for example, 15 ms. All the lines of data treatment is carried out on 128 passes of a particular cycle of recovery. This means that every 1.92 ms (128x15 us) read all the strings in memory for data recovery.
Recovery of memory, unfortunately, takes away time from the processor: each cycle for the duration of recovery takes a few CPU cycles. In the old computers cycles recovery could take up to 10% (or more) of CPU time, but in the advanced systems that operate at a frequency equal to hundreds of MHz, the costs for recovery of 1% (or less) of CPU time. Some systems allow you to change the characteristics of the regeneration using the installation program performance CMOS, but the increase in the time between regeneration cycles may lead to the fact that some memory cells charge "drain", and it will cause disruption of memory. In most cases, more reliable, or adhere to the recommended default refresh rate. Since the cost recovery in advanced computers are less than 1% change in frequency recovery is not significant impact on the properties of the composite. One of the species is considered applicable to the use of memory timings default or automatic settings, data with Setup BIOS. Most of the advanced systems do not allow to modify the timing of memory installed permanently using automatic parameter settings. Auto-install the motherboard reads the timing characteristics of the system determine the sequence in the ROM (serial presence detect - SPD) and sets the frequency of the periodic supply of pulses in accordance with the received payment dannymi.Operativnaya
In DRAM devices for storing one of bit uses only one transistor and two capacitors, so they are more roomy than other types of memory chips. Currently, there are chip DRAM 1 GB or more. This means that these chips contain a billion transistors. In my memory all the transistors and capacitors are placed follower but typically the nodes of a square grid, in the form of a very common, repetitive structures.
Transistor for each one-bit register DRAM is used to read the status of the adjacent capacitor. If the capacitor is charged, the cell write 1, and if there is no charge - recorded 0. Charges in tiny capacitors always trickles, that is why memory should continuously regenerated. Even a momentary power interruption, or any interruption in the recovery cycle will lead to loss of charge in the cell DRAM, and, consequently, to the loss of data. On a running system similar results in a "blue" screen, a global security system failures, corrupted files, or to the absolute failure of the system.
Dynamic random access memory used in personal computers, since it is cheap, chips can be tightly packed, and this means that the mass storage can occupy a small space. Unfortunately, this type of memory is the same as the highest performance, traditionally it is much "slower" processor. Therefore, there are many different types of organization DRAM, allowing to increase this feature!
Random access memory, or RAM - this is one of the main elements of a computer. "Operational" memory because it is very fast acting and allows the processor with little or no noticeable wait to read the information from the memory. Contained in the RAM data is stored and accessed only when the computer is turned on. When you turn off the computer contents erased from memory, because before you turn off all Computer data should be preserved. The amount of RAM (by the way, it is called RAM - random access memory) depends on the number of tasks that can simultaneously make Comp.
Operational pamyatOperativnaya memory - a work area for the CPU computer. In it during store programs and data. Memory is often regarded as temporary storage, because the data and the program in it saved up only when the computer or before pressing the reset button (reset). Before turning off or by pressing the reset button, all data subject to change at work, you need to save to the memory, which can store information permanently (usually a hard disk). With the new power-stored information can then be loaded into memory.
Device memory storage devices are sometimes called random access. This means that access to the data stored in memory, does not depend on their order in it. When they say the memory companies, traditionally involve memory, especially the memory chips or modules, which contain the active programs and data used by the processor.
Within a few years the definition of RAM (Random Access Memory) reincarnated common abbreviation of the term, which means the main working area of memory chips produced DRAM (Dynamic RAM - DRAM) and used by the processor to run programs. One of the properties of circuits DRAM (and, therefore, memory in general) is a dynamic data storage, which means, first, the possibility of multiple entries of information in memory, and, secondly, the need to keep the data (ie, in fact, their dubbing) approximately every 15 ms (milliseconds). There is also the so-called static RAM (Static RAM - SRAM), which does not require constant updating. It should be noted that the data is preserved in the memory only when the power is on.
By computer memory RAM traditionally assumed (RAM), ie physical memory of the system, which consists of chips or memory used by the processor to store the key, running at the current time code and data. With this, the term "data warehouse" refers not to the memory, to devices such as hard drives and tape drives (which, however, can be used as a type of RAM, dubbed virtual memory).
The term "memory" often means not only the chips that make up the memory device in the system, but also includes such thing as a logical mapping and placement. Logical mapping - a method of the address memory chips actually installed. Accommodation - this location is disk imaging (data and instruction) of a particular species to specific addresses memory.
While the program in memory saved up its data. Chip memory (RAM) is sometimes called volatile memory: after turning off the computer data stored in them will be lost if not previously saved to disk or other external memory device. To avoid this, some applications automatically make backup copies of the data.
Files computer program when it starts, it loads into RAM, which saved up while working with this program. The processor executes the software implemented commands in memory, and stores the results. Memory stores the codes which the keys are working with a text editor, but also the value of mathematical operations. When you click Save (Save) the contents of memory is saved as a file on your hard drive.
The physical memory in the system is a set of chips or modules containing the chips, which are traditionally connected to the system board. These chips or modules can have different properties and in order to function correctly, must be compatible with the system, which are established.
In advanced computers used memory devices 3 main types:
ROM (Read Only Memory). Only Memory - ROM is not able to do the operation data recording.
