What principle and the role of flash memory?

works flash memory
　　flash memory, also known as flash memory (flash memory), an electrically erasable programmable read only memory in the form of a plurality of times can be rubbed or write operation, EEPROM and RAM become the most commonly used high-speed and the fastest growing of two storage technologies. The computer's BIOS, a digital camera memory card uses flash memory. The main features of flash memory in case of power failure can not long retain stored information. By its nature the flash memory belonging to EEPROM (electrically erasable programmable read only memory) type. It has both ROM features, there are high access speed, and easy to erase and rewrite, low power consumption. At present degree of integration reached 4MB, while prices also declined. Due to the unique advantages of flash memory, such as the use Flash ROM BIOS in some newer motherboard BIOS will make very easy to upgrade. a solid-state flash memory can be used as mass storage.
　　At present large-capacity hard disk memory is still widely used. Although the hard disk capacity and low-cost advantages, but it is an electromechanical device, the mechanical wear, relatively poor reliability and durability, impact resistance, resistance to vibration is weak, a large power consumption. Therefore I have been hoping to find a means to replace the hard drive. Since Flash Memory integration continue to improve, continue to lower prices, it replaced the small-capacity hard drive on the laptop has become possible. Currently the development of flash memory are in line with the PCMCIA standard, can be very convenient for a variety of portable computer to replace the disk. There are currently two types of PCMCIA cards, known as Flash memory card, bank card, only Flash Memory chips require special software to manage the use Shihai. Another called Flash driver card, the control circuit card, in addition to this there is a Flash chip microprocessors and other logic circuits thereof. They are compatible with the IDE standard, such as a hard disk can be directly operated as under DOS. So often refer to them as Flash SSDs. flash memory deficiencies capacity is still not big enough, the price is a little expensive side. Thus reliability required for the main light-weight high, but the capacity is not a portable system. In the microcomputer 586 Yiba Flash BIOS resident in the system memory.
flash memory effect:
　　FLASH memory also called the flash memory is a nonvolatile long life (can maintain stored data in case of power failure) memory. Because it can still save the data when powered down, the flash is generally used to save the settings information such as the computer's BIOS (basic input output program), PDA (personal digital assistants), digital cameras save information.
　　Unlike the other hand, flash RAM (Random Access Memory) as a unit of rewriting data in bytes, and therefore can not replace LFASH RAM. It combines the advantages of RAM and ROM, electrically erasable programmable only has performance data will not be lost when power also can read data quickly, U disk and MP3 in this memory is used. In the past two decades, embedded systems typically use ROM such as EPROM, etc. as their storage device, in recent years, Flash ROM memory full status instead of the embedded system, Bootloader and used as a storage operating system or program code, or when the hard disk directly.
　　In short FLASH memory because of its small size and large capacity fast speed, and does not require power to maintain the characteristics of the information stored is widely used in mobile storage, MP3 players, digital cameras, handheld computers and other emerging digital devices.