> It's been a long journey, but I'm almost there.
> 
Well struggled. It is often worth the eductaional side effects.

> If I comment out "#USE_NANDECC = -DCONFIG_YAFFS_USE_NANDECC" in my YAFFS 
> Makefile, then my files are read back correctly. The only thing 
> that happens 
> now is that I get that "Reading data from NAND FLASH without ECC is not 
> recommended" warning message BUT my system appears to be working.
> 
> I am guessing that the ECC stuff is being handled twice or it is being 
> mishandled somewhere when I define CONFIG_YAFFS_USE_NANDECC. Comments?
> 
That is precisely what I do and I comment out the MTD whinge. It is clearly important that SOMEONE does the ECC and it is a mild pity that the MTD layer assumes that only it is competant to do so.

It is probably that yaffs should get the MTD layer to do its ecc eventually as standard.

Nick