[t10] op x23 of PDT x00 practically not vendor-specific

[Pat LaVarre]

* From the T10 Reflector (t10 at t10.org), posted by:
* "Pat LaVarre" <LAVARRE at iomega.com>
*
> From: [offline]
 
Sorry I was unclear, thanks for saying I was.
 
I imagine PDT x00 with RMB clear gets affected by SFF by way of hosts supporting PDT x00 with RMB set but thinking that RMB set implies PDT x05.
 
I don't yet myself intimately know any PDT x00 with RMB clear.  I have not yet seen any such device implement op x23.  But that doesn't let me disavow that rumour that Microsoft is sending that op.  For example, I may have been told that the HDD respond SK ASC = x 5 20 Unsupported Op, I no longer remember clearly.  So long as I believe Microsoft is sending the op, I will recommend against giving op x23 any other vendor-specific meaning, which in mind empties the merely public Ans claim that op x23 is vendor-specific.
 
I have studied only a few PDT x00 with RMB set in detail.  The ones I studied did implement op x23.  That suggests someone somewhere thought the implementation was necessary, but that someone may have been misinformed.
 
The web trail:
http://www.bswd.com/cornucop.htm
ftp://ftp.seagate.com/sff/INF-8070.PDF
yields "9.7.10 READ FORMAT CAPACITIES Command" "Operation Code (23h)" required, in that context.
 
Clear now?  I'll drill down deeper offline, lucky you.
 
Pat LaVarre

	-----Original Message----- 
	From: Pat LaVarre 
	Sent: Mon 4/7/2003 4:33 PM 
	To: t10 at t10.org 
	Cc: 
	Subject: RE: [t10] op x23 of PDT x00 practically not vendor-specific
	
	

	* From the T10 Reflector (t10 at t10.org), posted by: 
	* "Pat LaVarre" <LAVARRE at iomega.com> 
	* 
	> so technically speaking, our merely public PDT x00 
	> standard is not incorrect. 
	  
	Ouch.  I was hoping this was an RMB issue only. 
	  
	Offline kindly I'm told Microsoft's Win XP 
	sends op x23 Read Format Capacities 
	to non-removable HDD as well. 
	  
	Ouch. 
	Ouch. 
	Ouch. 
	  
	Pat LaVarre 

	        -----Original Message----- 
	        From: Pat LaVarre 
	        Sent: Tue 4/1/2003 5:21 PM 
	        To: t10 at t10.org 
	        Cc: 
	        Subject: RE: [t10] op x23 of PDT x00 practically not vendor-specific 
	        
	        

	        * From the T10 Reflector (t10 at t10.org), posted by: 
	        * "Pat LaVarre" <LAVARRE at iomega.com> 
	        * 
	        Help?  I'm not sure what you mean. 
	          
	        If you will allow me to misquote some ' ' as '.' I can 
	        say in http://www.t10.org/lists/op-alph.htm I see: 
	          
	        as of 2/11/03 
	        ..  DTLPWRSOMCAEBK 
	        23  .....O........  READ FORMAT CAPACITIES 
	          
	        I think R = O means op x23 is not vendor-specific for 
	        PDT x05 = R.  I agree with that, sure, but I mean to 
	        be saying op x23 isn't really vendor-specific for PDT 
	        x00 = D. 
	          
	        Ok, so technically speaking, our merely public PDT x00 
	        standard is not incorrect. 
	          
	        We can say some host vendors who massively distribute 
	        their stuff have chosen to ab/use PDT x00 op x23 in a 
	        certain way and a large number of device vendors have 
	        chosen to play along with this ab/use. 
	          
	        But we might confuse less people if we change the next 
	        rev of SBC to admit that here the de facto PDT x00 
	        standard has departed from the de jure PDT x00 standard. 
	          
	        Personally I'm vague on the proper spec-ese.  We need 
	        a polite way to say, uh, yea, we stole a 
	        vendor-specific op back, sorry about that. 
	          
	        Rather than baldly stealing it back, maybe we should 
	        just add an implementation note: "Some SBC device 
	        vendors choose to define the vendor-specific op x23 as 
	        MMC does." 
	          
	        No? 
	          
	        Cluelessly, curiously, thankfully yours, Pat LaVarre 

	                -----Original Message----- 
	                From: David Dillard [mailto:david.dillard at veritas.com] 
	                Sent: Tue 4/1/2003 5:09 PM 
	                To: Pat LaVarre; t10 at t10.org 
	                Cc: 
	                Subject: RE: [t10] op x23 of PDT x00 practically not vendor-specific 
	                
	                

	                You would seem to be correct.  See http://www.t10.org/lists/op-alph.htm 
	                
	                
	                
	                > -----Original Message----- 
	                > From: Pat LaVarre [mailto:LAVARRE at iomega.com] 
	                > Sent: Tuesday, April 01, 2003 6:11 PM 
	                > To: t10 at t10.org 
	                > Subject: [t10] op x23 of PDT x00 practically not vendor-specific 
	                > 
	                > 
	                > * From the T10 Reflector (t10 at t10.org), posted by: 
	                > * "Pat LaVarre" <LAVARRE at iomega.com> 
	                > * 
	                > http://www.t10.org/scsi-3.htm 
	                > ftp://ftp.t10.org/t10/drafts/sbc2/sbc2r08.pdf 
	                > 
	                > "The following operation codes are vendor-specific: 
	                > 02h, 05h, 06h, 09h, 0Ch, 0Dh, 0Eh, 0Fh, 10h, 11h, 
	                > 13h, 14h, 19h, 20h, 21h, 22h, 23h, 24h, 26h, 27h, 
	                > 29h, 2Ch, 2Dh, and C0h through FFh." 
	                > 
	                > Except for op x23 we're just kidding.  "Everybody 
	                > knows" RMB PDT x00 often needs op x23 to mean Read 
	                > Format Capacities, as in the SFF 8070i Compaq LS-120 specification. 
	                > 
	                > Have we (T10) ever discussed acknowledging this fact in SBC? 
	                > 
	                > Should we? 
	                > 
	                > Cluelessly, curiously, thankfully yours, Pat LaVarre 

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