Flash memory is one of the most user friendly types of memory found in the marketplace at this time. It's made of two principal types, NOR Flash and NAND flash. These titles are based on the type of logic gate which is used in all of the memory cells. NOR flash memory got its start from Intel in 1988, followed by NAND flash in 1989, introduced to the world by Toshiba.
With NOR flash, there is the ability to have random access of any memory location by utilizing full addresses and data busses. No more moving parts to slow you down as it is with RAM. This rapid flash memory has its problems too.
It has long write and long erase times and it is more expensive than its NAND counterpart. You will most often come across NOR flash in things like cell phones, where large files are normally uploaded and then subsquentially replaced. It works off of an SRAM interface that has a variety of address pins so it can map its entire media and allow access to every byte within it. NOR flash is the leader in the industry in memory capacities from 1-16 Mbytes while NAND is used up to 128 Mbytes. This exhibits why NOR is a more effective match for code storage while NAND is mostly used for data storage and can be generally found in the sector that produces memory cards for games, cameras and MP3 players. When it comes to ease of use, NOR flash certainly wins hands down.
It can be connected in a very straightforward manner directly like any other memory device item and code run straight from it. Then again, with NAND, the use and ease of use is totally dependent on the NAND vendor because it also requires an I/O interface. Writing information to the NAND flash is a complex process where virtual mapping should always be into position on the NAND device.
In certain devices, NOR and NAND work in conjunction. For instance, you might find that a pocket PC would utilize both forms of flash memory to operate. It might use NOR to boot the OS and a memory card that is removable for your memory or storage requirements.
One can also find both types of memory products in a digital camera. The NOR flash would hold the camera's software while the NAND might be found in the removable photo card. Unfortunately, the long term outlook of NOR flash is quite poor at present.
With the cheaper NAND cards and the capability to construct phones with NAND, NOR is a lesser competitor than it was five years ago. You can still find several uses for NOR flash with certain suppliers, but the bankruptcy of key vendors of NOR Flash has temporarily set the once bright flash memory back and pushed NAND to the forefront of the marketplace, with other types like SPI flash bringing up the rear.
Bernard Hoyt spent some time working at a company that provides and components for commercial, vehicular, wifi, and consumer electronics markets. He writes regarding the changes and advancements that often occur in the industry as well as the trends in the developing IT industry.