+++ Nick Bane [04-09-17 11:56 +0100]:
> > Lately there was an announcement of the new Toshiba E830 with
> > 64MB NOR-Flash.
> > The old version had 32MB NAND and 32MB NOR FLASH.
> > In the article it says that now the programms can run directly from FLASH.
> >
> I think it means that one can run 64MB xip apps not 32MB+32MB data.
> > - Is that corret? Is it only possible to run programms from NOR Flashes?
> NOR is typically memory mapped, NAND is serial (except for first page of new 16-bit nands after a power cycle reset)
>
> > - If yes, why dosen't we use NOR Flash instead of NAND?
> > - Because of the price?
> Yes.
> Erase/write times to NAND are actually a lot faster than with NOR too.
> Also, NOR is really slow so its fine for executing boot code but in reality anything running at PDA speeds needs to execute out of ram - unless it small enough to fit in the cache I suppose.
There is a useful summary of NOR/NAND differences in this slide:
http://www.aleph1.co.uk/talks/yaffs/mgp00005.html
(anyone got updates for the prices quoted there? - they have no doubt changed since 2001)
WHich comes from here:
http://www.aleph1.co.uk/yaffs/jffs2_and_nand.html
This study is now somewhat dated (it was written in 2001 and JFFS2 has since
acquired NAND support), but the hardware comparison remains valid.
Wookey
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