Thread: Memory Types
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Old 06-01-2008, 04:29 AM
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Re: Memory Types

Quote:
Originally Posted by TurboFool View Post
It's ALSO too slow. It's like using it as virtual memory. It's roughly comparable to the speed of a hard drive, which is the very reason we still have RAM and don't just access everything from the hard drive. ROM is absurdly slower than RAM, and our phones would be painful to use if we tried to use ROM as virtual memory. But yes, it ALSO has a limited number of writes.
Quote:
Originally Posted by gguruusa View Post
It's not that it's too slow (although it is very slow in comparison), it's that flash has a limited number of times you can write to it. If you treat flash like RAM, you will soon have a brick.
actually, its not that its too slow, part of it is that NAND flash requires block addressing, and RAM is byte adressable, which would make it useless as RAM, since to write/read 18 random bytes, you might have to read 18 different blocks, and if your blocksize is something like 64kb, thats 1MB of reads for 18 bytes! note that NOR flash is capable of byte addressing... but its more /expensive/slower, but can be used to full XIP.
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