RE: [Yaffs] Yaffs on SD memory / CF card

YAFFS is designed for NAND flash, but has also been used on NOR flash
and even as a RAM fs as well.

NAND flash is available in "raw" form as either solder down devices or
in SmartMedia and XD memory cards.

Compact Flash indeed has NAND or NOR inside, but the CF also has a built
in controller that does error correction etc. CF does not have the
concept of "blocks". The same goes for USB pendrives etc.

YAFFS needs the spare area in each NAND page to write tags etc. This is
simulated in NOR flash implementations (how to do this has been outlined
in previous postings - along with warnings etc).

You could potentially do the same thing with Compact Flash, but you
would not get any of the YAFFS robustness.

I have not analysed SD cards, but I think they have an onboard
controller which also makes them like Compact Flash.

If you want to use customer-loadable storage with YAFFS, then I suggest
SmartMedia or XD.





-----Original Message-----
From: yaffs-admin@stoneboat.aleph1.co.uk
[mailto:yaffs-admin@stoneboat.aleph1.co.uk] On Behalf Of Abhishek
Bhattacharya
Sent: Monday, 21 February 2005 9:42 p.m.
To: yaffs@stoneboat.aleph1.co.uk
Subject: [Yaffs] Yaffs on SD memory / CF card


Hello

Has anyone ever tried mounting yaffs on a SD memory card or for that
matter on any Compact flash card?
Just eager to know about the scope of yaffs outside normal NAND flash

regards
Abhishek