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On 4/15/02, Hale replied to Pat > >.... > >Lets see your proposal. > >But let me make a try at it... > >Hale's proposal follows: Should Hale get a document number??? > >.... > NO!!! In my opinion, no change is required, because I still don't see anything broken. The example Pat has given is for the Inquiry command, where the additional length field is in byte 5 of the returned data. As Hale explained, Host suppliers have no problem accepting 6 bytes when they only needed 5 bytes. Better yet, they usually REQUEST six bytes even though they only need 5 bytes. The hosts ALWAYS leaves room in their buffers for that extra byte. And there is ONLY 1 extra byte for 16 bit transfers, regardless of the transfer mode -- PIO, SWDMA, MWDMA, UDMA -- all the same. The only thing I would propose is to explicitly tell the device suppliers to round the byte count UP to the next word size and explicitly warn the host suppliers to allow room in their buffers to accomodate the 'round-up' to the next word boundary. Again, better yet, the host can be advised to simply round the byte count up in the CDB (in case the device rounds down). ...Harlan
