Flash memory is considered the most user friendly kinds of memory sold in the marketplace right now. It's made up of two main types, NOR Flash and NAND flash. These names are derived from the type of logic gate that is used in each of the memory cells.
Flash (NOR) got its start from Intel in 1988, and then NAND flash in 1989, brought to the world by Toshiba. With NOR flash, you have the ability to have random access of any memory location by employing full addresses and data busses. There are no moving parts to slow you down as it is with RAM. This rapid flash memory does have its down side too. It has long write and long erase times and it is higher in price than its NAND counterpart.
You will usually see NOR flash in items like cellphones, where sizeable files are often uploaded and then subsquentially replaced. It works off of an SRAM interface which has a variety of address pins so that it can map its total media and allow access to every byte within it.
NOR flash is the leader in the industry in memory sizes from 1-16 Mbytes while NAND can be used up to 128 Mbytes. This demonstrates why NOR is a more effective fit for code storage while NAND is mostly used for data storage and can be generally found in the market that manufactures memory cards for games, cameras and MP3 players.
In relation to ease of use, NOR flash surely wins every time. It can be connected in a very uncomplicated way directly like any other memory device item and code run straight from it. Then again, with NAND, the use and ease of use is very dependent on the NAND vendor since it also requires an I/O interface. Writing information to the NAND flash is a difficult process where virtual mapping should always be into position on the NAND device.
In some units, NOR and NAND work in conjunction. For instance, you might find that a pocket PC may use both kinds of flash memory to operate. It would use NOR to boot the OS and a memory card that is removable for any memory or storage requirements. An individual may also find both kinds of memory technologies in a digital camera. The NOR flash would hold the digital camera's software while the NAND would be found in the removable photo card.
Unfortunately, the long term outlook of NOR flash is rather dim at this time. With the less expensive NAND cards and the ability to develop mobile phones with NAND, NOR is a lesser rival than it was 5 years ago.
You can still find some uses for NOR flash with certain manufacturers, but the bankruptcy of key distributors of NOR Flash has for the time being set the once bright flash memory back and sent NAND to the head of the industry, with additional types like SPI flash bringing up the rear.
Flash (NOR) got its start from Intel in 1988, and then NAND flash in 1989, brought to the world by Toshiba. With NOR flash, you have the ability to have random access of any memory location by employing full addresses and data busses. There are no moving parts to slow you down as it is with RAM. This rapid flash memory does have its down side too. It has long write and long erase times and it is higher in price than its NAND counterpart.
You will usually see NOR flash in items like cellphones, where sizeable files are often uploaded and then subsquentially replaced. It works off of an SRAM interface which has a variety of address pins so that it can map its total media and allow access to every byte within it.
NOR flash is the leader in the industry in memory sizes from 1-16 Mbytes while NAND can be used up to 128 Mbytes. This demonstrates why NOR is a more effective fit for code storage while NAND is mostly used for data storage and can be generally found in the market that manufactures memory cards for games, cameras and MP3 players.
In relation to ease of use, NOR flash surely wins every time. It can be connected in a very uncomplicated way directly like any other memory device item and code run straight from it. Then again, with NAND, the use and ease of use is very dependent on the NAND vendor since it also requires an I/O interface. Writing information to the NAND flash is a difficult process where virtual mapping should always be into position on the NAND device.
In some units, NOR and NAND work in conjunction. For instance, you might find that a pocket PC may use both kinds of flash memory to operate. It would use NOR to boot the OS and a memory card that is removable for any memory or storage requirements. An individual may also find both kinds of memory technologies in a digital camera. The NOR flash would hold the digital camera's software while the NAND would be found in the removable photo card.
Unfortunately, the long term outlook of NOR flash is rather dim at this time. With the less expensive NAND cards and the ability to develop mobile phones with NAND, NOR is a lesser rival than it was 5 years ago.
You can still find some uses for NOR flash with certain manufacturers, but the bankruptcy of key distributors of NOR Flash has for the time being set the once bright flash memory back and sent NAND to the head of the industry, with additional types like SPI flash bringing up the rear.
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