Computers and any electronics are complex devices whose operating principles are not always clear to most ordinary people. What is ROM and why is a device necessary? Most people will not be able to answer this question. Let's try to fix this misunderstanding.
What is a ROM?
What are they and where are they used? Permanent storage devices (ROM) are non-volatile memory. Technologically, they are implemented as a microcircuit. At the same time, we learned what the acronym ROM is for decryption. Devices for storing user input and installed programs are designed. In the permanent storage device you can find documents, melodies, pictures - i.e. everything that should be stored for months or even years. The amount of memory, depending on the device used, can vary from a few kilobytes (on simple devices having one silicon crystal, microcontrollers for example) to terabytes. The larger the volume of the ROM, the more objects can be saved. Volume is directly proportional to the amount of data. If you compact the answer to the question, what is ROM,should answer: thisA data warehouse that is independent of DC voltage.
Hard drives as primary read-only memory devices
The question of what ROM is already answered. Now we should talk about what they are. The main permanent storage device is hard drives. They are in every modern computer. They are used due to their wide possibilities of accumulating information. But at the same time, there are a number of ROMs that use multiplexers (these are microcontrollers, boot loaders, and other similar electronic mechanisms). With a detailed study, it will be necessary not only to understand the value of ROM. Decoding of other terms is also necessary in order to delve into the topic.Expanding and complementing ROM capabilities with flash technology
If the user does not have a standard amount of memory , then you can take advantage of the additional expansion of the capabilities of the ROM provided in the field of data storage. This is done through modern technologies implemented in memory cards and USB-flash drives. They are based on the principle of reusable use. In other words, the data on them can be erased and recorded tens and hundreds of thousands of times.
What is a permanent storage device?
The ROM contains two parts, which are designated as ROM-A (for storing programs) and ROM-E (for issuing programs). Type A read-only memory is a diode-transformer matrix, which is flashed using address wires. This ROM section performs the main function. The filling depends on the material from which the ROMs are made (perforation and magnetic tapes, punch cards, magnetic disks, drums, ferrite tips, dielectrics and their property of the accumulation of electrostatic charges can be used).Schematic structure of ROM
This electronics object is depicted as a device, which in appearance resembles the connection of a certain number of one-bit cells. The ROM chip, despite the potential complexity and seemingly significant capabilities, is small in size. When storing a specific bit, it is sealed to the case (when zero is recorded) or to the power source (when one is recorded). To increase the capacity of the memory cells in read-only memory devices, microcircuits can be connected in parallel. This is what manufacturers do to get a modern product, because a high-performance ROM chip allows them to be competitive in the market.The amount of memory when used in various units of technology
The amount of memory varies depending on the type and purpose of the ROM. So in simple household appliances such as washing machines or refrigerators, you can have enough installed microcontrollers (with their reserves of several tens of kilobytes), and in rare cases, something more complex is installed. It does not make sense to use a large amount of ROM, because the amount of electronics is small, and the technology does not require complex calculations. For modern TVs, something more advanced is already required. And the pinnacle of complexity is computing technology such as computers and servers, ROMs for which, at a minimum, can accommodate from a few gigabytes (for those released 15 years ago) to tens and hundreds of terabytes of information.Masked ROM
In cases where recording is carried out using the metallization process and a mask is used, such a permanent storage device is called masked. The addresses of the memory cells are fed to 10 pins, and a specific chip is selected using a special CS signal. Programming of this type of ROM is carried out at the factories; as a result, manufacturing in small and medium volumes is disadvantageous and rather inconvenient. But with large-scale production, they are the cheapest among all permanent storage devices, which ensured their popularity., , . , , . , . , , . .
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