Re: cdrecord and scsi-3 compliance
>From: Andy Polyakov <appro@fy.chalmers.se>
>> >> In any case, the low level transport code needs to set the lun bits
>> >> if the SCSI level is <= 3.
>>
>> >Not '<=', but '<'. A.
>>
>> Well, SCSI-3 did not include this new feature in the beginning,
>Define "beginning." First draft or first ratified specification? Can you
>really confirm that 3 most significant bits of second byte of command
>block were still LUN in first ratified document?
Except for SCSI-1, I know of no SCSI standard that has ever been used
from aproved versions.
The background is that getting a "final" versions costs money while
the drafts are free. Also drive manufacturers are most often faster than
the standard... SCSI-3 is now in progress since more than 4 years.
I am sure that the LUN bits have not been redifined in the first version.
>> so
>> any firmware that enforces the lun field to be zero for SCSI-3 is broken.
>No, it's not. "Recipients *may* check reserved bits, bytes, words or
>fields for zero values and report errors if non-zero values are
>received."
As you cannot check whether a drive supports an early SCSI-3 draft or a later
one, this incompatible change cannot be used before SCSI-4
Jörg
--
EMail:joerg@schily.isdn.cs.tu-berlin.de (home) Jörg Schilling D-13353 Berlin
js@cs.tu-berlin.de (uni) If you don't have iso-8859-1
schilling@fokus.fraunhofer.de (work) chars I am J"org Schilling
URL: http://www.fokus.fraunhofer.de/usr/schilling ftp://ftp.berlios.de/pub/schily
Reply to: