On Wednesday 14 February 2007 09:42, Brad Beveridge wrote: > In Yaffs terminology, a chunk is one page of NAND.  So you are > accessing the 19889th page on the device (19889/32 = block > 621). Without looking at the Yaffs code, I'm not 100% sure > what the ":1" part is - perhaps the byte address? A 512 byte page has two ECC units, the ":1" indicates which unit. Candru, I agree with Brad, until you have shown that the MTD interface is working correctly, there is really no point in trying Yaffs. And worse... If Read is broken but writing to oob/spare works, you might land up with large numbers of erroneous bad-block markers installed in your NAND. I always recommend disabling the bad-block marking in Yaffs and/or MTD when bringing-up new designs/drivers -- this requires some simpe hacking. Also keep a per-chip record of the factory-installed bad-block indicators before you start -- but this will require the MTD Read to operate first. If Read is broken, but erase is working, one could potentially erase the factory-installed bad-block indicators! On a new device, all data should Read 0xFF and only the blocks marked bad in the factory should have any zero bits in the oob/spare fields. So again, get MTD nand Read and nanddump working first. -imcd