Flash memoryis a kind of nonvolatile memorizer.
It can ensure the data safety even in case of power outages.
Flash memory is a variant of EEPROM (Electrically Erasable Programmable Read-Only Memory).
Unlike RAM which can rewrite data in bytes, flash memory cannot replace the RAM.
Flash card is a memorizer that adopts flash memory technology to store electronic information.
Though different in appearance and specification, these cards share the same technical principles.
Technical Features
Big differences lie in NOR and NAND flash memory.
The former one looks more like flash memory which has a separate address wire and data cable.
This kind of flash memory is expensive in price, but small in capacity.
The later one owns many characters we can find on a hard disk.
Its address wire and data cable are merged in an I/O line.
Whats more, it has more advantages in cost and capacity.
And it is often used to store the program codes which directly run in the flash memory.
Digital memory cards like flash drives and digital memory cards often use NAND flash memory to save data.
Whats more, the speed of the flash memory is limited.
And its operating speed and frequency is much lower than the internal memory.
The low operation efficiency of NAND flash memory is closely related to its architecture and interface design.
Characteristics of flash memory include fast access speed, no noise and small heat dissipation.
Users who ask for low disk capacity can buy flash memory card.
Instead, if you have high requirements on capacity, purchase hard disk which is much cheap per gigabyte.
Supplementary Instruction
1.
However, the NAND flash memorys fundamental memory cell is page.
The available capacity of each page is integer multiples of 512 bytes.
The so-called effective capacity refers to the data area plus 16 bytes parity information.
NAND flash memory often does the erase operations in the unit of sector.
Writing data into flash memory must be performed in the blank space.
If there is some data in the target area, you must do erase before writing.
Therefore, the erase operation is the basic operation of flash memory.
And each packet can transmit eight bit addressing information.
When transferring, it will be respectively grouped, which needs at least three times and occupies three cycles.
With the increase of capacity, address information will be more.
And it will take more time to do transmission.
It is directly inserted into the server, so the time used to receiving information will be greatly saved.
Advantages of Flash Memory
1.
Small in size (but not in low integration level).
Storing data in safe state, and reasons are as follows:
