directAccess mode page x1B

Pat LaVarre LAVARRE at
Thu Mar 14 16:24:35 PST 2002

* From the T10 Reflector (t10 at, posted by:
* "Pat LaVarre" <LAVARRE at>
I hear Scsi-over-whatever devices do commonly supply mode page x1B ...

I see Scsi 2 says this page code is Reserved.  I see SBC 3, "Revision 8c", "13 November 1997", "Table 73- Mode page codes" agrees.

Anybody care to resolve this conflict?

Maybe best by "obsolete"ing this code, when used by op x12 Inquiry (bytes[x00] & x1F) peripheralDeviceType = x00 directAccess?

Curiously yours,
Pat LaVarre   p.lavarre at

P.S. More specifically, I see Oct 1996 r1.1 SFF 8070i says page x1B is the "Removable Block Access Capabilities Page" which offers such tidbits as:


The Total LUN (TLUN) field specifies the total number of LUN supported by this Device. This is different from the Last LUN Identifier in Word 127 of Identify Device Information.

... [and also] ...

A System Floppy (SFLP) bit of one indicates that this device can be used as a system floppy device. This causes legacy issues to be invoked.

A Supports Reporting progress of Format (SRFP) bit of one indicates that the ATAPI Block Device shall be capable of receiving a FORMAT UNIT command with the Immediate bit set ... shall report ... FORMAT IN PROGRESS ...

A Non-CD Optical Device (NCD) bit ...

A Single/Multiple LUN supported (SML) bit of one indicates that this device is a phase change dual device and supports a CD device and a Non-CD Optical Device using the same LUN. Devices reporting a one in this bit will  change the device type and commands supported based on the type of media installed.


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