This message is from the T13 list server.

The costs to test the R/W long command are next to zero, as in unmeasureable, 
as is the cost of the hardware to implement it.  You need to attempt to find a 
different point on which to hang your hat.  And actually, there is not one 
available for you.

3/18/02 9:23:11 PM, "McGrath, Jim" <[EMAIL PROTECTED]> wrote:

>
>Don,
>
>"In initial debug there might be some issues (again of insignificant nature 
>compared to getting R/W and the rest of the drive working), but by the time
>a 
>drive goes into manufacturing, they will be resolved."
>
>You are sort of getting the point, but missing the message.  ANY costs are
>an issue today.  Costs are often viewed as opportunity costs.  i.e. not so
>much how much wages do I pay people, but rather how long this could delay a
>product and/or other developments for which (paying) markets have been
>identified.  As a simple example, a day late for us is over $1M short.
>Given that, engineers quite properly push back on any additional work
>required that could increase development time or even the risk of an
>increase in development time.
>
>Rather than dismissing the costs, which I don't think is a very convincing
>argument (especially to those incurring the costs), perhaps a better tack is
>to promote a proposal that has the potential to add revenue (via prcing or
>market size).  Unfortunately, that's pretty hard given the state of the
>industry, but I think it has a better chance of persuading people.  Indeed,
>past proposals that T13 has adopted generally have that in common (even 
then
>people are cautious about incurring costs).
>
>Jim
>
>
>-----Original Message-----
>From: don clay [mailto:[EMAIL PROTECTED]]
>Sent: Monday, March 18, 2002 5:53 PM
>To: McGrath, Jim
>Subject: Re: RE: RE: [t13] Re: RE: Re^10 R/W (Long) Commands
>
>
>The R/W Long command has a low probability of changing from drive to drive, 
>expecially on the testing side.  On the drive side, it should be independent
>of 
>addressing in that it  should use the drives common address handling
>routines.  
>In initial debug there might be some issues (again of insignificant nature 
>compared to getting R/W and the rest of the drive working), but by the time
>a 
>drive goes into manufacturing, they will be resolved.
>
>As I've indicated previously, the standards committee should have enough a 
>broad enough perspective to poll users of the standard so that it
>understands 
>what ALL users of the standard are doing before it makes a decision to 
>obsolete hardware and commands.  Not everyone who is using the standard 
>should have to come to every meeting out of self-defense.  
>
>Your example of converting to XP is not a relevant example.  Microsoft 
>continually makes changes that break current software.  That's why software 
>vendors list which of Microsoft's OS's on which their software will run.
>Microsoft 
>even has a program for the older versions of their OS that will tell you
>what 
>software and hardware will or will not run under XP.  To convert to XP can
>be a 
>very expensive proposition for people who have a lot of programs on there 
>computer.
>
>Furthermore, Microsoft has regularly changed file formats for even their own
>
>programs which force people to buy the latest and greatest versions of their
>
>software.
>
>Other industries have been very successful in accomodating backward 
>compatibility.  Sometimes, they even make it work for decades or centuries.
>
>Imagine that!
>
>3/18/02 6:13:20 PM, "McGrath, Jim" <[EMAIL PROTECTED]> wrote:
>
>>
>>Don,
>>
>>The problem is not the testing it is the extension or what happens if the
>>testing fails (i.e. what do you do)?  Given the changes to ATA addressing,
>>it's quite possible that people felt that in order to continue to make the
>>function useful you would end up either extending it and/or fixing it (or
>>explaining to customers why their old READ/WRITE LONG no longer works 
on
>>part of the disk drive).  
>>
>>Once again, I'm not privy to the details on this issue in T13, but I
>suspect
>>that the address change and the obsolescing of these commands were not 
>just
>>coincidences in time.
>>
>>Finally, you appear to believe that code, once written, will always work.
>>Since we tend to change the hardware that the code runs on every product
>>(and a lot of the other code that runs along with it), that's just not true
>>(we even change microprocessors and languages used to implement the 
>software
>>on occasion!).  
>>
>>To put it in a more familiar context, a lot of things that use to work fine
>>on older PCs running older OSes fail on newer PCs with newer OSes.  I just
>>installed Windows XP at home and had a really good time cleaning up
>>applications that ran fine on Windows 98 and no longer run on XP.  And this
>>is a market where Microsoft is being paid quite a bit of money to make
>every
>>attempt to preserve backward compatibility.
>>
>>So over time there is an excellent case to be made to obsolete some things
>>in the interests of making other things easier/cheaper to do - industries
>do
>>it all of the time.  Making that call at a particular point in time is up
>to
>>the suppliers of course - all obsolescing it in the standard does is to
>>allow them over time to make those decisions and still remain compliant
>with
>>the standard.
>>
>>Jim
>>
>>PS the T13 committee is an open standards body, with modest fee 
>requirements
>>(I think it may be $500 to $1000 total a year).  Not only companies belong,
>>but so do some individuals (usually as consultants in the industry).  If
>you
>>are interested in joining just go to the web site.  I've suggested several
>>times that people put together a proposal (all proposals are also on the
>web
>>site) to address any specific issue they want to see addressed.  Just
>asking
>>the committee to reverse itself is, I think, a strategy with a low
>>probability of success (since the decisions taken are typically not by
>whim,
>>but had some reasons behind them).
>>
>>-----Original Message-----
>>From: don clay [mailto:[EMAIL PROTECTED]]
>>Sent: Monday, March 18, 2002 4:33 PM
>>To: McGrath, Jim
>>Subject: Re: RE: [t13] Re: RE: Re^10 R/W (Long) Commands
>>
>>
>>Of course firmware testing is not trivial.  However, some parts of the
>>testing is 
>>trivial compared to other parts.  Verifying correct operation of the R/W
>>Long 
>>commands is trivial compared to data integrity testing or testing the
>>Security 
>>commands or testing the power commands or testing other specifics of the 
>>standard.   Changing the testing of this command from product to product 
>>requires NO changes to tests.The amount of time that goes into testing the 
>>R/W Long command is insignificant monetarily and as a percentage of the
>>total 
>>time used to verify the rest of the drive is functioning properly.  The
>>amount of 
>>hardware to support R/W Long is orders of magnitude less than the total of
>>the 
>>drive.
>>
>>Orders of magnitude more time is wasted waiting for the Host to 
acknowledge
>
>>interrupts than is used to test the R/W Long command.  Orders of magnitude 
>>more time is wasted on interrupt latency that is wasted testing the R/W
>Long
>>
>>command.  
>>
>>Removing firmware commands and hardware requires changes to these 
>>formware tests used to verify correct operation of the drive.  That does
>>cost 
>>money.  
>>
>>Obsoleting commands that are used by companies that are using this 
>standard 
>>exposes those companies who are using the obsoleted technology to the 
>>further whims of this committee.  
>>
>>I entered the thread with the point that obsoleting functions that were
>>currently 
>>in use is wrong.  It is so because BACKWARD COMPATIBILITY IS 
>>IMPORTANT.  It is so because people are using the R/W Long command.
>>
>>NOT LISTENING TO THE WHOLE OF THE PEOPLE ON THE BUS IS ALSO 
>>WRONG.   THOSE WITH NARROW PERSPECTIVES SHOULD NOT BE 
ON 
>>THIS COMMITTEE.  A STANDARD NEEDS TO ADDRESS THE 
>>PERSPECTIVE OF ALL THE USERS OF THE STANDARD AND NOT 
>>INDIVIDUAL SELFISH INTERESTS.    
>>
>>3/18/02 3:55:25 PM, "McGrath, Jim" <[EMAIL PROTECTED]> wrote:
>>
>>>This message is from the T13 list server.
>>>
>>>
>>>
>>>Don,
>>>
>>>Firmware testing is not trivial.  It can involve hundreds of systems
>>running
>>>for several weeks in an overworked compatibility lab.
>>>
>>>As long as the function in question was not changed (e.g. not updated for
>>>the new addressing system) or causes testing problems, these costs were
>>>folded into general firmware testing costs.  But remember that this whole
>>>thread began with people discussing the extension of these commands to 
>the
>>>new addressing system, which by definition is work and new testing.
>>Indeed,
>>>the new addressing extensions probably raised this whole issue originally
>>(I
>>>may be wrong - READ/WRITE LONG has had many detractors over the 
>years 
>>- but
>>>it would have prompted my concern).
>>>
>>>Remember that many of the uses (like marking a sector for later processing
>>>by the OS) do require the address extension.  Probably most manufacturers
>>>will continue to leave the command in there as is with no changes.  All
>>>obsolete means is that if extensions are desired or the function creates
>>>bugs, then the supplier has the option of not doing the work required and
>>>still remain ATA compliant.
>>>
>>>Jim
>>>
>>>PS Don, in general you should not be forwarding private communications to
>>>the reflector.  I'm a nice guy :-) , but a lot of others would take
>>>substantial offense.
>>>
>>>
>>>-----Original Message-----
>>>From: don clay [mailto:[EMAIL PROTECTED]]
>>>Sent: Monday, March 18, 2002 2:07 PM
>>>To: ata reflector
>>>Subject: [t13] Re: RE: Re^10 R/W (Long) Commands
>>>
>>>
>>>This message is from the T13 list server.
>>>
>>>
>>>Again, you are presenting arguments against testing of functions that are
>a
>>
>>>miniscule amount of testing, as in INSIGNIFICANT.  
>>>
>>>You have probably spent more engineering dollars on your replies to these 
>>>emails than would be spent over the lifetime of testing these functions
>>that
>>>you 
>>>have obsoleted. And these are functions that you have now admitted that 
>>some
>>>
>>>companies still use.
>>>
>>>Furthermore, other companies have said repeatedly that they still use
>them.
>>>
>>>
>>>3/18/02 2:02:28 PM, "McGrath, Jim" <[EMAIL PROTECTED]> wrote:
>>>
>>>>
>>>>Don,
>>>>
>>>>The problem is that today HDDs are increasingly viewed as a commodity,
>>with
>>>>no need for testability.  Of course some customers still want that
>>>>capability, but they are typically the larger OEMs (since they have the
>>>>resources to do the testing and have a lot to lose if a bad product
>>escapes
>>>>from them, so can afford the infrastructure required).  Even there, we do
>>a
>>>>lot of the testing that the OEMs use to do directly.
>>>>
>>>>Smaller customers typically buy through distribution.  Indeed, drive
>>>>suppliers often don't even know who these customers are (distributors do
>>>not
>>>>tell us).  Selling products through distribution has always been a less
>>>>technical sell than with OEMs, instead relying on basics like price and
>>>>promotions.
>>>>
>>>>The bottom line is that an abstract market pull has no effect on
>suppliers
>>>>if it is not economically visible to the suppliers.  If a supplier is not
>>>>rewarded for the work, but rather someone else in the distribution chain
>>>(or
>>>>just the end consumer) captures the reward, then there is no incentative
>>to
>>>>do the work.  BTW, this is a real common problem with "commodity"
>>products.
>>>>Everyone likes the low prices, intense competition, and standardization,
>>>but
>>>>they wonder why suppliers don't innovate except along the lines that they
>>>>will be compensated for (like higher drive capacity in the case of HDDs).
>>>>
>>>>On the work involved, the dominant work involving software is testing.
>>>This
>>>>is true for new code, and especially true for old code.  Whether the code
>>>>works or not, every time we change anything in software we have to re
>test
>>>>it.  And that costs time and manpower.  Money is saved by reducing these
>>>>tests costs.  Indeed, money is saved for customers as well, since if they
>>>>are doing testing they have to test less also.
>>>>
>>>>Over time commodity products reduce the number of features they offer 
>>(from
>>>>the earlier, non-commodity days) and instead focus on the "core" values
>of
>>>>the product.  By its nature the opposite - product differentiation -
>>occurs
>>>>when things get non commoditized, and suppliers can target specific
>market
>>>>niches and earn better returns by focusing product features to work well
>>in
>>>>those markets.  Today the HDD market is in a fairly heavy commoditization
>>>>mode, not a product differentiation mode.  I personally don't like that,
>>>but
>>>>I realize it.
>>>>
>>>>Unfortunately the thing that has been driving any investment in novel
>>>things
>>>>in HDDs - the prospect of expanding the market - is also not in good
>>shape.
>>>>We have a whole division set up to do HDDs for CE applications, and
>>another
>>>>for Network Storage Applications.  Neither has been as successful as
>>>>originally projected (e.g. PVRs still only sell in the hundreds of
>>>thousands
>>>>of units per year).  And the core PC and server markets have actually
>been
>>>>declining.  And the causes for all of this are not things we in the HDD
>>>>group can directly influence (like overall IT spending levels).
>>>>
>>>>Jim
>>>>
>>>>PS as to members of T13, you have to ask them what they do and why - 
I'm
>>>>sure there are differences among the members.  But since they all live in
>>>>the same economic sector, all of this sort of stuff drives their
>>businesses
>>>>to some degree.
>>>>
>>>>
>>>>-----Original Message-----
>>>>From: don clay [mailto:[EMAIL PROTECTED]]
>>>>Sent: Saturday, March 16, 2002 6:40 AM
>>>>To: McGrath, Jim
>>>>Subject: Re^10 R/W (Long) Commands
>>>>
>>>>
>>>>If the ATA committee had even approached the idealism that you espouse 
>in 
>>>>this last email, I wouldn't be contributing to this thread.
>>Unfortunately,
>>>>it doesn't.  
>>>>Nor is it close.  Except in the minds of the politically dominate
>>>>individuals (*NOT* 
>>>>companies) on this committee.  If you want examples of this, go re-read
>>>>emails 
>>>>posted to this Reflector... other than mine.
>>>>
>>>>Secondly,  testibility and marketability do contribute to the bottom
>line.
>>>>And 
>>>>they are accomodated in the design.  And a great deal of time and effort
>>>>does 
>>>>go into them in the design of the product.  And providing customers
>access
>>>>to 
>>>>testability is a marketing issue, as is backward compatibility.
>>>>
>>>>Thirdly, a lot of the stuff that would allow backward compatibility that
>>>has
>>>>been 
>>>>eliminated from the ATA specification is considerably less than 1% of
>>>either
>>>>the 
>>>>silicon and the software of a HDD.  SRAM & ROM costs are often 
irrevelant
>>>in
>>>>
>>>>these days.  For example a 2MB ROM might be considerably less cost 
than 
>a 
>>>>1MB ROM if the 2MB ROM has higher volumes.  So it is virtually impossible
>>>to
>>>>
>>>>make generalizations about these things.  And software costs are often
>>>times
>>>>
>>>>negligible for such things R/W Long.  Often times code that is written
>>once
>>>
>>>>carries over for several generations of drives without re-write.
>>>Especially
>>>>non-
>>>>performing commands such as R/W Long
>>>>
>>>>Fourthly, Innovation really has nothing to do with this thread.  I was
>>>>merely 
>>>>pointing out how the ECC command was (and still is being used according 
>to
>>
>>>>early contributors to this thread) capable of "completely" testing the
>ECC
>>
>>>>capability and how the R/W Long command can be used with negligible 
>>>>hardware and software costs. 
>>>>
>>>>3/14/02 12:18:22 PM, "McGrath, Jim" <[EMAIL PROTECTED]> wrote:
>>>>
>>>>>
>>>>>Don,
>>>>>
>>>>>Companies are focused on profits since that is the function.  Other
>types
>>>>of
>>>>>organizations (schools, government, churches) rightly deal with other
>>>>>aspects of life.  And T13's members are companies, not individuals.
>"I'm
>>>>>shocked, truly shocked" that a company might be concerned about 
profits
>>>>:-).
>>>>>
>>>>>Doing the work you describe does cost a company money (e.g. skilled
>>>>>engineering labor), and it does show up on the radar map.  I know, since
>>>>I'm
>>>>>been involved in way too many of those conversations internally.
>>>>>
>>>>>Once again, the problem is that designing something in the standards
>>>>>committee reduces the ability of anyone to make a profit, and so reduces
>>>>the
>>>>>incentative for companies to make the required investments.  The
>original
>>>>>intent of the ATA standard in particular was to document what had
>already
>>>>>been in existence.  It was not originally intended to drive innovation.
>>>>>That does not stop people from trying to innovate in the standards
>>>>>committee, but its not the optimum mechanism to employ for innovation.
>>>>>
>>>>>Note that many folks involved in other standards bodies (like IEEE)
>don't
>>>>>understand some of this since they operate quite differently.  IEEE
>>>members
>>>>>are individuals, not companies.  The usual tradeoff is that the "ANSI
>>>>>standards" get a lot of industry support, since they are driven by
>>>>>companies.  A number of standards developed without that sort of 
support
>>>>>never get good industry adoption - but they often have more intellectual
>>>>>innovation.
>>>>>
>>>>>Jim
>>>>>
>>>>>
>>>>>-----Original Message-----
>>>>>From: don clay [mailto:[EMAIL PROTECTED]]
>>>>>Sent: Thursday, March 14, 2002 8:12 AM
>>>>>To: ata reflector
>>>>>Subject: Re: RE: RE: [t13] R/W Commands
>>>>>
>>>>>
>>>>>This message is from the T13 list server.
>>>>>
>>>>>
>>>>>Let's see.  If you add a vendor unique command to enable a special, but
>>>>very
>>>>>
>>>>>simple piece of software, you can make R/W long transfer all the ECC
>>>bytes.
>>>>>
>>>>>This requires no additional hardware, but you have to be thinking about
>>it
>>>>>when 
>>>>>you design your ASIC.  Very simple, very complete, and it works.
>>>>>
>>>>>All I can about the rest of your reply is that it has been my experience
>>>>>that, as in 
>>>>>the example above, it is possible to design in to a HDD testibility and
>>>>>flexibility 
>>>>>without costing anything that would show up on the radar screen.  
>>>>>
>>>>>It has been a shame that the political controllers of this interface
>have
>>>>>enforced 
>>>>>these types of limitations in their big desire to * "FIX" * the
>interface
>>>>>for the profit 
>>>>>of their company or the imagined screws that they are applying to the 
>>>>>competition or NIH.  
>>>>>
>>>>>This has been in lieu of attempts at understanding what the original
>>>>>designers 
>>>>>of the interface had in mind.  It has also, at times, neglected to look
>>at
>>>>>the big 
>>>>>picture of other devices that might co-exist on this interface, such as
>>>>CD's
>>>>>or 
>>>>>DVD's (or where they are designed).
>>>>>
>>>>>There has been significant innovation on the interface, however, and
>>there
>>>>>has 
>>>>>always been room for it.  A very great example of which was implemented
>>by
>>>
>>>>>your old company, Quantum, with the development of Ultra DMA.  The 
>>>>interface
>>>>>
>>>>>could have been evolved with these innovative new ideas without making
>>old
>>>
>>>>>drives obsolete.
>>>>>
>>>>>And this would all be water under the bridge if the committee wasn't
>>still
>>>>>doing 
>>>>>the same thing.
>>>>>
>>>>>
>>>>>3/13/02 7:35:02 PM, "McGrath, Jim" <[EMAIL PROTECTED]> wrote:
>>>>>
>>>>>>This message is from the T13 list server.
>>>>>>
>>>>>>
>>>>>>
>>>>>>Don,
>>>>>>
>>>>>>You can't really completely test ECC today with the limited
>capabilities
>>>>of
>>>>>>the READ/WRITE long commands.  The problem is that only 4 bytes of 
>the 
>>>>>much
>>>>>>longer ECC field can be modified, so that in essence some of the data
>>(at
>>>>>>this level user level and ECC are both "data") simply cannot be
>modified
>>>>>via
>>>>>>the interface.
>>>>>>
>>>>>>As for Big Blue, the reward they got was quite large for compatibility.
>>>>>>This is very high margin territory (i.e. big systems, like mainframes).
>>>>>But
>>>>>>ongoing support and testing costs were also high.  At the end of the
>day
>>>>>>customers paid enough in higher prices to offset the higher costs and
>>>make
>>>>>>it worthwhile for IBM.
>>>>>>
>>>>>>The problem is that none of this is true in the PC industry, and
>>>>especially
>>>>>>for the HDD segment of it.  Personally I would like nothing better than
>>>to
>>>>>>produce non commodity HDDs that offer lots of extra value for the
>>>customer
>>>>>>and sold for a higher price that both covered my cost and made me a
>>>>profit.
>>>>>>Unfortunately, that's extremely difficult to do today given how the PC
>>>and
>>>>>>HDD industry have been structured.
>>>>>>
>>>>>>Jim
>>>>>>
>>>>>>PS the savings in obsolescing functions over time is to reduce the
>>>>>>development and support costs for those features.  Every product (we 
do
>>>>>>several a year) requires that we test the features and make any
>>>>adjustments
>>>>>>to make them work.  In absolute terms the costs are not huge, but given
>>>>the
>>>>>>financial health of the HDD industry it shows up on our radar.
>>>>>>
>>>>>>
>>>>>>-----Original Message-----
>>>>>>From: don clay [mailto:[EMAIL PROTECTED]]
>>>>>>Sent: Wednesday, March 13, 2002 8:17 AM
>>>>>>To: ata reflector
>>>>>>Subject: Re: RE: [t13] R/W Commands
>>>>>>
>>>>>>
>>>>>>This message is from the T13 list server.
>>>>>>
>>>>>>
>>>>>>This is a reply to Jim McGrath's email which is included below for
>>>>>>reference.
>>>>>>
>>>>>>Even in 1986, SCSI had a significantly smaller market share than the
>PC,
>>>I
>>>>>>don't 
>>>>>>remember the exact numbers.  Like I said, ATA devices were mostly 4 
>>bytes
>>>>>>until 
>>>>>>about 1989, 1990.  
>>>>>>
>>>>>>But that doesn't really matter.  The real point is that people had
>>>figured
>>>>>>out how 
>>>>>>to use R/W Long for *completely* being able to test ECC regardless of
>>how
>>>
>>>>>>many bytes of ECC there were.  And it is still being done.  And has
>also
>>>>>>been 
>>>>>>pointed out, R/W Long is still being used, maybe not by your company or
>>>>any
>>>>>>of 
>>>>>>the "politically significant" people on the committee, but by several
>>>>other
>>>>>
>>>>>>vendors.  Enough so that the command should not have been 
obsoleted.
>>>>>>
>>>>>>Please cite what the Big Blue big price for compatibility was.  It
>>>>would've
>>>>>>cost 
>>>>>>significantly more for the companies to replace their software if that
>>>>>>compatibility 
>>>>>>would NOT have been maintained.  And the same is true for the PC.  
>>>>Although
>>>>>>it 
>>>>>>IS true that a certain individual has gotten extraordinarily rich by
>>>>>>regularly 
>>>>>>obsoleting his own software.  (I wonder if there are any numbers
>showing
>>>>>how
>>>>>>
>>>>>>much of Americas GNP has been wasted by this individual in this
>>>endeavor.)
>>>>>>
>>>>>>The hardware and software to implement R/W Long is insignificant 
>>>compared 
>>>>>to
>>>>>>
>>>>>>the rest of the hardware and software.  It can be handled as a special
>>>>case
>>>>>>in 
>>>>>>the course of normal R/W code and hardware.  
>>>>>>
>>>>>>Providing testability is a necessity in an interface.  If you look at
>>the
>>>>>>totality of the 
>>>>>>hardware and software that were included in the orginal interface for
>>>>>>testability, 
>>>>>>it is insignificant compared to the functional hardware and software.
>>>>>>
>>>>>>There is no valid reason to obsolete much of what has been obsoleted
>>>>except
>>>>>
>>>>>>for NIH, politics, and short sightedness on the part ATA committee.  
>>>>>>Repeatedly, stuff has been obsoleted over the objections of other
>>>>companies
>>>>>
>>>>>>on the interface.  
>>>>>>
>>>>>>There is also no valid reason why a 1986 model drive should not be able
>>>to
>>>>>>be 
>>>>>>plugged on to a cable with a 2002 model drive and be able to boot and
>>>>work.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>3/12/02 6:52:31 PM, "McGrath, Jim" <[EMAIL PROTECTED]> 
wrote:
>>>>>>
>>>>>>>This message is from the T13 list server.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>Don,
>>>>>>>
>>>>>>>In 1986 I worked on our Q200 product, with used a 96 bit Reed-
>Solomon 
>>>>>ECC
>>>>>>>code.  It was a high volume product (it was sold to Apple for the Mac
>>>>>among
>>>>>>>others). Once again, this was made possible by embedding the 
>controller
>>>>>>into
>>>>>>>the HDD.
>>>>>>>
>>>>>>>My mental database does not go back that far for competitor drives,
>but
>>>>>I'm
>>>>>>>sure they were, well, competitive :-).  If you can cite differently
>>>>please
>>>>>>>do.  
>>>>>>>
>>>>>>>As to IDE (actually, ATA - that the standard, you are probably
>thinking
>>>>of
>>>>>>>the "vendor unique" interface I mentioned), I know exactly when it
>>>>started
>>>>>>>since I actually started it (well, along with Dal Allen).  The intent
>>>was
>>>>>>>actually to standardize what was then known as the "Conner 
>compatible"
>>>>>>>interface, based on the earlier vendor unique work done by a multiple
>>of
>>>>>>>folks at IBM, CDC, WD, and Compaq.  We did not complete ATA-1 
until 
>>>>1990
>>>>>>>(you can still get a copy off of the T13 web site).
>>>>>>>
>>>>>>>At the time we did not even think much about this issue - the merging
>>of
>>>>>>>drive and controller was still fresh in people's mind, and eliminating
>>>>>>these
>>>>>>>commands would have been a bit premature.  After that inertia took
>>over.
>>>>>>>T13 really did not get into the habit of obsolescing things for quite
>>>>some
>>>>>>>time.  Note that ATA-1 and ATA-2 themselves are now obsolete (i.e.
>>>>>>withdrawn
>>>>>>>standards).
>>>>>>>
>>>>>>>I don't dispute that vendor unique commands to test a lot of things
>>work
>>>>-
>>>>>>>we have commands that bypass defect management, allow you to 
>create 
>>>>and
>>>>>>>erase servo bursts, etc...  But they are not made available to
>>customers
>>>>>>and
>>>>>>>so the ATA READ/WRITE LONG commands have nothing to do with 
>>that.
>>>>>>>
>>>>>>>On correction spans, you have not been able to test the correction
>>>>ability
>>>>>>>of the ECC for at least 10 years.  Once you are restricted to just
>>>>>>modifying
>>>>>>>a subset of the ECC field (and not even a well documented specific
>>>>subset)
>>>>>>>there are just some testing you cannot perform. 
>>>>>>>
>>>>>>>Partially testing a drive vendors ECC is sort of silly, since we
>>>>>completely
>>>>>>>test it (using vendor specific commands).  Indeed, while customers
>were
>>>>>>>initially nervous when we started doing ECC on drives (afterall, we
>had
>>>>>not
>>>>>>>done it before), by 1990 I don't know of a single customer who thought
>>>>>that
>>>>>>>was a big issue (at least with our drives).  Today some of the best
>ECC
>>>>>>>people in the world work at disk drive companies - testing our ECC is
>>>>sort
>>>>>>>of like testing PW50.  Customers who understand these issues make 
>>sure 
>>>>we
>>>>>>>run the appropriate tests - they don't rely on their own testing to
>>>>verify
>>>>>>>things at this level (they may do that sort of testing, but they don't
>>>>>rely
>>>>>>>on it).  BTW, the ECC on a drive is being constantly employed for both
>>>>>>>detection and correction.  It's not like it's some idle circuitry you
>>>>have
>>>>>>>to exercise.
>>>>>>>
>>>>>>>As for Big Blue, you forget to mention that that software
>compatibility
>>>>of
>>>>>>>30 years comes as a big price.  And Intel was trying to protect the
>>>>>>>investment in an applications software base of over 10,000 programs, 
>>and
>>>>>>>were rewarded quite well for that.  If people are willing to pay for
>>>that
>>>>>>>degree of compatibility, the market will provide.  Conversely, if they
>>>>are
>>>>>>>not providing it, then the market is simply not willing to pay for it.
>>>>>>>
>>>>>>>Jim
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>-----Original Message-----
>>>>>>>From: don clay [mailto:[EMAIL PROTECTED]]
>>>>>>>Sent: Tuesday, March 12, 2002 2:42 PM
>>>>>>>To: ata reflector
>>>>>>>Subject: [t13] R/W Commands
>>>>>>>
>>>>>>>
>>>>>>>This message is from the T13 list server.
>>>>>>>
>>>>>>>
>>>>>>>The following statements are NOT true.
>>>>>>>
>>>>>>>1.  I think you're missing the point.  For more than a decade ECC
>>fields
>>>>>>>have
>>>>>>>been longer than 4 bytes.  Basically the READ/WRITE LONG 
>commands 
>>>>>have 
>>>>>>>not been valid for their original purpose for at least that long,
>>>>probably
>>>>>>>longer.  Indeed, I don't think they have been valid since drive
>>>>>>>manufacturers began integrating the controller onto the drive (i.e.
>the
>>>>>>>entire lifetime of the ATA standard, going back to ATA 1).
>>>>>>>
>>>>>>>Note - ECC lengths of greater than 4 bytes were not prevalent until
>>>quite
>>>>>>>some 
>>>>>>>time (3 or 4 years minimum) after the IDE came into existance.
>>>>>>>
>>>>>>>2.  Remember that ATA was a standardization of what was originally a
>>>>>vendor
>>>>>>>unique interface developed in the days when controller boards and 
>HDDs 
>>>>>were
>>>>>>>separate devices (i.e. the early 80's).  At that time such a function
>>>>make
>>>>>>>sense.  When the two were combined, this original purpose lost its
>>>>>meaning.
>>>>>>>
>>>>>>>Note - Testing of correction spans and limits continued way beyond
>this
>>>>>>>point.  
>>>>>>>Additionally, with the use of vendor unique commands, ECC testing 
has 
>>>>>>>remained valid.
>>>>>>>
>>>>>>>3. Actually, all HDD ECCs are vendor unique - their length is not
>>>>>standard,
>>>>>>>and
>>>>>>>going forward it's not even clear that ECC will be linked with 512
>byte
>>>>>>>sectors.  And unless you know the codes being used, trying to test it
>>is
>>>>>>>pretty useless (the drive itself, and certainly the manufacturing
>>>>process,
>>>>>>>does a better job).
>>>>>>>
>>>>>>>Note- Again with vendor unique commands, ECC testing remains valid.  
>>No 
>>>>>>one 
>>>>>>>has time in the manufacturing process to do anything more than verify
>>>>>basic
>>>>>>
>>>>>>>funcrtionality of ECC.
>>>>>>>
>>>>>>>Furthermore the following statement is easily disputable with the
>>>>>following
>>>>>>>two 
>>>>>>>examples.  If Intel had taken the approach of the ATA committee,
>>>software
>>>>
>>>>>>>would have become obsolete with each new generation of processor.  
If 
>>>>IBM 
>>>>>>>had taken this approach, the big box would not still be alive after 30
>>>>>>years
>>>>>>>as 
>>>>>>>their software would have been repeatedly obsoleted.  It is only the
>>>NIH,
>>>>>>>politics, 
>>>>>>>and short sightedness of the ATA committee that has prevented a 
drive
>>>>that
>>>>>>>ran 
>>>>>>>in 1990 or EVEN from 1986 from being able to be put on a 2002 PC.
>>>>>>>
>>>>>>>If anything, the ATA committee is way too slow in obsoleting
>functions!
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>
>>
>>
>
>
>



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