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> > Scsi read/write/readCapacity ops
> > that can carry more than 32 bits of Lba
...
> "Mcgrath, Jim" <[EMAIL PROTECTED]> 02/14/02 07:01PM
> the latest draft of
> the Block Command Set for SCSI (on www.t10.org)
> contains support for 8 byte (64 bit) LBAs.
Thanks for the pointer.
> The real issue is software implementation, ...
> ... And the installed base of software ...
...
> > [x88] Read(16)
> > [x8A] Write(16)
> > [x8E] WriteAndVerify(16)
> > [x8F] Verify(16)
Looks like t10, as yet, has required devices that need 64 bit Lba's ...
... to learn to move out 16 byte Cdb's.
For Atapi as published this means beginning to exercise the long unused SixteenByteCdb
option of x0001 = (op xA1 Identify "word" 0 & x0003). For Usb, the long unused option
of xC < bCBWCBLength. And so on.
> [x2B] SEEK(10)
Looks like nobody's bothering to upgrade the Seek command to allow 64 bit Lba's. (Not
that I see op x8B in use yet.)
> > READ CAPACITY needs more work
...
> 5.1.10 [x25] READ CAPACITY command
...
> ... [bytes[1] & x02] ... LONGLBA bit ...
...
> ... [Editor's note: 01-267 proposes
> to eliminate the LONGLBA bit
> here in favor of a separate READ CAPACITY (16) command.]
Sensible yes, but, like you say, apparently not yet stable.
Fun to see Scsi adopting the Ata idea of multiple inequal capacities: given
0.5KiB/block then anything above 2TiB will report both the xFF:FF:FF:FF expressible in
four bytes and a larger true maxLba.
> (3) If any of [x 0A 2A AA] WRITE (6)/(10)/(12)
> is implemented, [x8A] WRITE(16)
> shall also be implemented.
Somebody's pushing hard. I see the xA8/AA Read12/Write12 forms that raise the
maxBlockCount above xFF:FF for maxLba at or below xFF:FF:FF:FF are optional, but the
x88/8A Read16/Write16 forms that raise the maxLba above xFF:FF:FF:FF are "mandatory".
> Thanks for the pointer.
I'm guessing you meant the SBC-2 that includes a dedicatory colour snapshot of Gene
Milligan i.e. the last of the trail:
http://www.t10.org/
Draft Standards and Technical Reports
http://www.t10.org/drafts.htm
Command Sets
http://www.t10.org/drafts.htm#CMNDSETS
SCSI-3 Block Commands (SBC)
1997/11/13, Rev: 08c
ftp://ftp.t10.org/t10/drafts/sbc/sbc-r08c.pdf
SCSI Block Commands - 2 (SBC-2)
ftp://ftp.t10.org/t10/drafts/sbc2/sbc2r04.pdf
2001/07/28, Rev: 04
Pat LaVarre
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