ROM is a kind of random memory, it can be divided into what is wrong?

ROM (Read-Only Memory) is a solid-state semiconductor memory that can only read out previously stored data. ROM is mainly composed of address decoder, memory body, readout line and readout amplifier and other parts, the data stored in it is stable, and the stored data will not change after power failure, and the structure is relatively simple, easy to use, so it is often used to store various fixed programs and data.

The data stored in the ROM is generally written in advance before loading the whole machine, and can only be read out during the working process of the whole machine, unlike random access memory, which can be quickly and easily rewritten. The data stored in the ROM is stable, and the data stored in the ROM will not change after the power is off; Its structure is relatively simple and easy to read, so it is often used to store various fixed programs and data. Except for a few types of read-only memory (such as character generators) that can be universalized, the content of read-only memory required by different users is different.

In order to facilitate use and mass production, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM) and electrically erasable programmable read-only memory (EEPROM) have been further developed. For example, the boot program (operating system) of early personal computers such as Apple II or IBM PC XT AT, or the firmware in various other microcomputer systems

ROM: Only random messages can be read out.

The main differences between Read-Only Memory (ROM) and Random Access Memory (RAM) are:

1. Different meanings 1. ROM is the abbreviation of read-only memory, which is a kind of solid-state semiconductor memory that can only read out the data stored in advance. 2. RAM is random access memory, also known as main memory, which is the internal memory that directly exchanges data with the CPU. Second, the role is different: 1, the main role of the read-only memory is to complete the power-on self-test of the system, the initialization of each functional module in the system, the basic input and output drivers of the system and the boot operating system.

2. RAM is the internal memory that directly exchanges data with the CPU. It can be read and written at any time, and it is fast, often as a temporary data storage medium for the operating system or other running programs. 3. The characteristics of the two are different: 1. The ROM memory can only be read, it only allows a chance to write once it is produced, and the data cannot be changed once it is written.

Another feature of the memory is that the data inside is not lost after the memory is powered off. 2. RAM can be read and written at any time, and the data saved on it will automatically disappear after power failure.

You can only read out guesses and can't write information.

The data stored in the ROM is stable and determined, and the data stored after power failure will not change, and the structure is relatively simple and easy to use, so it is often used to store the fixed programs and data of each punch index. The characteristic of ROM is that it can only read out and cannot write information, and usually solidifies a basic input-output system in the ROM of the computer motherboard, called BIOS (Basic Input and Output System). Its main function is to complete the power-on self-test of the system, the initialization of each functional module in the system, the driver of the basic input and output of the system and the boot operating system.

A ROM is a solid-state semiconductor memory that can only read out data stored in advance. It is characterized by the fact that once the information is stored, it cannot be changed or deleted. It is usually used in electronic or computer systems that do not require frequent data changes, and the data does not disappear due to power off.

RAM is a random access memory, and it is divided into two types: (B)).

RAM is further divided into static RAM.

Static RAM (SRAM) and Dynamic RAM (DRAM).

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ROM is composed of the initials of Read Only Memory, which means read-only memory. As the name suggests, this is the kind of memory that can only be read and cannot be read and written at any time like RAM. It only allows one write opportunity after it has been produced, and the data cannot be changed once it is written.

Another feature of the memory is that the data inside the memory is not lost after the power is off, and it can be stored for hundreds of years.

In order to store data persistence, ROMs are often used to store important information about the computer, such as the BIOS (Basic Input and Output System) of the computer motherboard. Unlike RAM, the data stored in the ROM is theoretically permanent.

Even after the computer is shut down, the data saved in the ROM will not be lost.

The information stored in the BIOS controls the operation of your computer system. Because of its importance, unauthorized copying or deletion of the BIOS is not allowed. However, there are some different types of ROMs that can be updated for a particular requirement.

1: ROM - This is the standard ROM that is used to store important data permanently. When a technical product needs some of its information to not change with changes in external factors and other factors, they usually use this standard ROM module.

In a ROM, the information is permanently etched into the ROM unit, making it impossible for the ROM to change the information in it after the etching has been completed.

2: PROM (Programmable ROM) - This type of ROM works similarly to CD-R, it allows you to rewrite the data in it once, remember: the data is rewritten only once.

Once the information is written to the PROM, the data is permanently etched into it, and the PROM is no different from the ROM described above.

3: EPROM (Erasable Programmable ROM) - Of course, EPROM can do this when the data stored in the ROM needs to be erased or rewritten. Irradiating this type of ROM with UV light can erase the data in it, and it also allows the information you need to be stored in such ROMs.

4: EEPROM (Electrically Erasable Programmable ROM) - This type of ROM is now commonly used in the BIOS of computer systems, it is very similar to EPROM, and the information in EEPROM can also be erased and new data can be written to it. As its name suggests, for this EEPROM we can use electricity to erase it without the need for ultraviolet light, which is very useful for the motherboard's BIOS.

Based on the principles described above, motherboard manufacturers can release their latest BIOS for users to upgrade the motherboard's BIOS, and the way to do this is to use the BIOS update program to generate electrical signals to freshen the information in the BIOS.

ROM: Only random messages can be read out.