Should Immed bit be validated by FOV?

Gerry Houlder Gerry_Houlder at
Fri Nov 3 09:08:12 PST 1995

The FORMAT command defect list header has a Format Options Valid (FOV) bit that 
is supposed to be set whenever the initiator wishes to change one of the 
standard format option bits. The original intent was that the Vendor Specific 
bit was not validated by this bit but all of the standard bits were. The 
description in the standard lists the DPRY, DCRT, STPF, IP, and DSP bits as 
being validated by the FOV bit but the Immed bit is not listed.

I believe that this was an oversight. When the Immed option was added to 
FORMAT, it should have been added to the list of bits that are "validated" by 
the FOV bit. Does anyone object to making this change in SBC?

There is always the chance that the Immed bit was intentionally defined so that 
it is not validated by the FOV bit. If anyone believes this to be the case, why 
should this bit be treated differently than the other standard option bits?

How about real implementations? For products that support the Immed option, do 
they validate the bit with FOV or not? Any feedback on this issue will be 

This issue will be discussed at the SCSI working group next week. John 
Lohmeyer, will you please add this issue to the agenda?

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