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RE: FAT32 over NAND


> > YAFFS2 is not a possible option...As device should also be able to
> > access on Windows PC using mass storage interface...

You could build a FAT emulation layer in memory and map the calls through to
YAFFS2, but that's a non-trivial task.

> Is this a raw flash? So, how is it going to be accessed from Windows if
> the file system is completely in software?

Windows basically wants to treat NAND (eg. SD) just like any other disk and
wants to deal with it as sectors.
There's a minimal amount of glue necessary between the given SD interface and
eCos's disk layer.  Then you just have to 
[have/get/write] a USB mass storage endpoint driver.

Where you're going to run into trouble is if you have the device accessing
the file system at the same time that the PC (eg. Windows) is trying to.
The FAT tables are cached on Windows, and if you go change them from the
device side underneath Windows (eg. eCos app modifies file system while it's
mounted on Windows), 
you are heading for disaster.  The reason I raise this issue is because you
mentioned wanting both your device and Windows to be able to see the same
file system.

--Chris

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