Article directory
When I was doing questions on the principles of computer composition, I found that I lacked some understanding of the concepts of RAM and ROM. After reading some articles and feeling that I understood them, I made this record.
If there are any errors, please point them out!
Concept combing
CPU
CPU, also called Central Processing Unit (Central Processing Unit), is the computing core and control core of a computer.
The CPU consists of arithmetic units, controllers and main memory. There are CPUs in computers and mobile phones.
The CPU is part of the host computer.
Main storage/memory/RAM/memory
主存储器It consists of memory banks, MAR and MDR, and is also part of the host.
Main memory is also called 内存, usually referred to as RAM.
RAM, Random Access Memory (Random Access Memory) is a type of main memory.
运存It is a folk name for memory. The professional term memory has never existed in the professional field, just because people who don’t understand call external memory (internal storage) memory, and memory is called memory.
ROM
ROM, Read-Only Memory, is a type of memory. Its chip is usually included in the motherboard of the computer system and is not in the main memory, which means that RAM and ROM are separate.
ROM was not writable at first, but later developed ones can be read and written, such as UV-erasable EPROM and electrically erasable EEPROM.
Secondary memory/external memory
Secondary memory is also called external memory (storage space). Unlike main memory, which is part of the host, it is part of the I/O device.
Hard drive (computer), flash memory (mobile phone)
It is implemented by the hard disk in the computer, and it is implemented by the flash memory in the mobile phone, that is, flash memory, which is a kind of ROM and can be read and written.
So the question is, why do computers use hard drives to store data, and why do mobile phones not use hard drives but use flash memory?
1、The larger storage space and cost-effectiveness of hard drives are more suitable for the storage needs of computers, while mobile phone users do not have such a large demand for storage space.
2、Flash memory has fast read and write speeds, which can provide fast application loading and file transfer speeds, which is crucial for mobile phone users. The read and write speeds of hard disks are relatively slow. For computer users, generally The file transfer speed can meet daily needs.
3、Flash memory is less susceptible to damage and more durable than hard drives, making it suitable for portable mobile devices such as mobile phones.
4、Flash memory usually has lower power consumption and smaller size and is suitable for mobile devices such as mobile phones, while hard disk memory has larger size and power consumption and is more suitable for computers.
5、In terms of price, generally speaking, the price of hard drives is relatively low, while the price of flash memory is relatively high.
GPU
A GPU is the main graphics processing chip on a third-party graphics card or motherboard, which is the chip.
Video memory
Video memory, also called frame buffer, is used to store rendering data that has been processed or is about to be extracted by the graphics card chip. Like a computer's memory, video memory is the component used to store graphics information to be processed.
Schematic diagram of the internal structure of the mobile phone for reference
The picture comes from: [Science Popularization] A brief discussion of mobile phone flash memory & memory - Mobile phone technology video detailed explanation No. 9 Shengli Produced
This is the end