Hi all, We are using a flash card with 32 KB page size and hardware generates ecc for every 512 bytes . There is extra 8 bytes available for storing meta information for the 512 bytes It is not possible to directly write on to the spare area. As I understand, we can ask yaffs to use in-band tags for every 512 bytes. Is it required for the driver to implement the write_oob or write_ecc function for mounting yaffs ?. Of the mtd functions, read, write, erase, write_oob ,read_oob, sync and mark_block_bad , we have implemented the basic read write and erase. What other functions are absolutely essential for using yaffs and which can be stubs?. Thanks, mugunthan