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dahlem 05-30-2008 04:49 PM

Memory Types
 
What are exactly the differences in the memory types? I show . . .

Program Memory @ 49%
Storage Memory @ 12%
Extended ROM @ 74%

Can the Storage Memory be somehow manipulated over to the Progam Memory?

Mogul Running no2chem 5068

Thanks for any input!

vetvito 05-30-2008 06:07 PM

Re: Memory Types
 
Ram
Rom
Rom

Nope, too slow for read and write.

gguruusa 05-31-2008 01:03 PM

Re: Memory Types
 
Quote:

Originally Posted by vetvito (Post 300145)
Ram
Rom
Rom

Nope, too slow for read and write.

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.

TurboFool 05-31-2008 01:06 PM

Re: Memory Types
 
Quote:

Originally Posted by gguruusa (Post 300734)
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.

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.

no2chem 06-01-2008 04:29 AM

Re: Memory Types
 
Quote:

Originally Posted by TurboFool (Post 300738)
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 (Post 300734)
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.

gguruusa 06-01-2008 07:41 AM

Re: Memory Types
 
Quote:

Originally Posted by TurboFool (Post 300738)
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.

If it didn't have a # of writes limitation, you can bet it'd be used for virtual memory. Slow virtual memory is loads better than no virtual memory.

GoodThings2Life 06-01-2008 07:47 AM

Re: Memory Types
 
So how many times is it going to be repeated that it's too slow and like virtual memory? :P

In any case, gguruusa is right, it's still a better option. That's one reason of many why it has never gone away from Windows.


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