MMC/Mt Fuji: Clarification about R and RW/Rewritable profiles
Bill McFerrin
billmc37 at ctesc.net
Fri Oct 20 08:17:05 PDT 2006
* From the T10 Reflector (t10 at t10.org), posted by:
* Bill McFerrin <billmc37 at ctesc.net>
*
Dear David,
I agree that it is not reasonable and I agree that poor wording (for
which I am responsible) has probably caused some confusion, but given
our weak definition of profile, it is permitted.
Bill
David Burg wrote:
> * From the T10 Reflector (t10 at t10.org), posted by:
> * David Burg <daviburg at windows.microsoft.com>
> *
> Ouch indeed,
>
> So you mean that a DVD-ROM drive shall never report the DVD+R/RW profiles?
Because we at Microsoft have a failure in our tests precisely because of such
DVD-ROM drives.
>
> Best regards,
>
> David Burg.
>
> -----Original Message-----
> From: Bill McFerrin [mailto:billmc37 at ctesc.net]
> Sent: Thursday, October 19, 2006 7:05 AM
> To: David Burg
> Cc: mtfuji5 at avc-pioneer.com; t10 at t10.org
> Subject: Re: MMC/Mt Fuji: Clarification about R and RW/Rewritable profiles
>
> Ouch,
> It gets worse. The paragraph below the DVD+RW Profile states that the
> Write bit must be set to one. I will be posting rev 4 this weekend with
> fixes based upon the ANSI editor's comments. The clarification here is
> to remove the footnotes that cause confusion.
>
> Kind Regards,
> Bill
>
>
> David Burg wrote:
>
>> * From the T10 Reflector (t10 at t10.org), posted by:
>> * David Burg <daviburg at windows.microsoft.com>
>> *
>> Hi Bill,
>>
>> You said: "Each DVD+ profile requires the ability to record."
>>
>> But the spec says in a note for the write features of the + profiles: "1
This feature is mandatory only when the Write bit of the DVD+RW Feature is
set to one."
>>
>> Does DVD+ profile really require the ability to record?
>>
>> Best regards,
>>
>> David Burg.
>>
>> -----Original Message-----
>> From: Bill McFerrin [mailto:billmc37 at ctesc.net]
>> Sent: Wednesday, October 18, 2006 4:16 PM
>> To: David Burg
>> Cc: mtfuji5 at avc-pioneer.com; t10 at t10.org
>> Subject: Re: MMC/Mt Fuji: Clarification about R and RW/Rewritable profiles
>>
>> Hi David,
>> There is less to this than you think.
>>
>> In the beginning (sort of), there was DVD-ROM and no writables. Some
>> DVD-ROM drives rejected recorded DVD+RW discs (and sometimes others as
>> well). We wanted a simple way for a DVD-ROM Drive to claim the ability
>> to read recorded DVD+ discs. Each DVD+ feature followed that idea for
>> consistency.
>>
>> Each DVD+ profile requires the ability to record.
>>
>> That's it.
>>
>> Kind Regards,
>> Bill McFerrin
>>
>> David Burg wrote:
>>
>>
>>> * From the T10 Reflector (t10 at t10.org), posted by:
>>> * David Burg <daviburg at windows.microsoft.com>
>>> *
>>> Dear Peter, All,
>>>
>>> I am reading mmc5r03c.pdf. This is the latest MMC 5 document on
www.t10.org
>>>
>>> Thank you Peter for the clarification. However something does not add up:
there is a delta between the DVD-ROM profile mandatory features and the
DVD+RW profile mandatory features, not only write features (20h and 23h), and
DVD+RW feature (2Ah), but also DCBs (10Ah). This is more than DVD-ROM
capabilities so I question that the spec sentence "If the Write bit is set to
zero, then no additional capability is claimed." really means not additional
capability but DVD-ROM read is claimed. I think it means instead, no
additional capability than claim until here in this feature definition.
Likely referring to the feature introduction "The presence of the DVD+RW
Feature indicates that the Drive is capable of reading a recorded DVD+RW disc
that is formatted according to [DVD+Ref2]."
>>>
>>> Now we could approach the problem differently than splitting hairs and
trying to second-guess the meaning of the sentences, and try instead to
specify what is the actual drives on market behavior. You say that most ROM
drives won't see blank and +R/RW features and profiles don't change that.
Maybe we need a clarification sentence in the specification of the +R/RW
features, rewording the introductions sentences:
>>>
>>> "The presence of the DVD+RW Feature indicates that the Drive is capable
of reading a recorded DVD+RW disc that is formatted according to [DVD+Ref2].
Recognition of blank DVD+RW disc is guaranteed only if the write bit of this
feature is set to one."
>>>
>>> Btw, there is an inconsistency between the RW and the R feature
specification wording. Only the R feature says "Specifically, this includes
the capability of reading DCBs."
>>>
>>> Best regards,
>>>
>>> David Burg,
>>> Microsoft.
>>>
>>> -----Original Message-----
>>> From: owner-mtfuji5 at avc-pioneer.com
[mailto:owner-mtfuji5 at avc-pioneer.com] On Behalf Of Peter Van Hove
>>> Sent: Tuesday, October 17, 2006 2:19 PM
>>> To: mtfuji5 at avc-pioneer.com; t10 at t10.org
>>> Subject: Re: MMC/Mt Fuji: Clarification about R and RW/Rewritable
profiles
>>>
>>> Dear David, All,
>>>
>>>
>>>
>>>
>>>> If I correctly understand your analysis, you analyzed the capabilities
>>>> claim from the DVD+R/W *feature(s)*.
>>>>
>>>>
>>>>
>>> I mentioned both, as both can only live together. If the plus profile is >>> reported the plus features will be present as well.
>>>
>>>
>>>
>>>
>>>> "A device may report this feature only when Profile 10h (DVD-ROM) is
>>>> reported"
>>>>
>>>>
>>>>
>>> Yes, as in, a drive that can't read DVDs can also not read DVD+R/W discs.
>>> I interpret that as, a drive must be a DVD ROM capable drive to be able
to
>>> do DVD+R/W.
>>>
>>>
>>>
>>>
>>>> And in the profile definition, the additional commands support is listed >>>> as mandatory. ("Drives identifying Profile 001Ah as current shall
support
>>>> the features listed in Table 221.")
>>>>
>>>>
>>>>
>>> I'm not using the same rev as you do, as it's table 220 in my spec :)
>>> But I'm not sure what you mean ?
>>> All it says is what features should be supported.
>>> And the features that are write related have a small uppercase 1 next to
>>> them, indicating:
>>> "1 This feature is mandatory only when the Write bit of the DVD+RW
Feature
>>> is set to one."
>>>
>>> So the presence of the plus R/W profiles does not guarantee the
availability
>>> of features that deal with writing, only those that deal with reading.
>>> And hence no guarantee that commands such as "Read Disc Information" are
>>> supported, which you need to be able to recognize blank media.
>>>
>>>
>>>
>>>
>>>> Would it be correct then to say that a DVD-ROM that want to claim only
>>>> recognition of DVD+R/RW but *not* of additional commands has to list
only
>>>> the DVD-ROM profile and the DVD+R/RW feature(s) but *not* list the
>>>> DVD+R/RW profile(s)?
>>>>
>>>>
>>>>
>>> I think that a DVD-ROM drive that either does or doesn't support the +R/W >>> profiles (and features) doesn't need to support the special commands that >>> you need to determine blank media.
>>>
>>>
>>>
>>>
>>>> I still don't know actually if this would mean that blank DVD+R/RW media >>>> are recognized or not.
>>>>
>>>>
>>>>
>>> Bet on the fact that 99% of the ROM drives won't see blank media.
>>> And the availability of plus R/RW features and profiles is no indication
nor
>>> guarantee that the drive can recognise blank media.
>>>
>>>
>>>
>>>
>>>> would it be correct to claim that devices claiming DVD+R/RW support have >>>> to support blank DVD+R/RW also?
>>>>
>>>>
>>>>
>>> No, only if they set the write bit to one.
>>>
>>> Best Regards,
>>> Peter
>>> -------------------------------------------------------
>>> Peter Van Hove, CEO Smart Projects
>>> CD and DVD Data recovery
>>> Peter at Smart-Projects.net
>>>
>>> www.Smart-Projects.net
>>> www.IsoBuster.com
>>> -------------------------------------------------------
>>> ----- Original Message -----
>>> From: "David Burg" <daviburg at windows.microsoft.com>
>>> To: "Peter Van Hove" <Peter at Smart-Projects.net>;
<mtfuji5 at avc-pioneer.com>;
>>> <t10 at t10.org>
>>> Sent: Tuesday, October 17, 2006 10:30 PM
>>> Subject: RE: MMC/Mt Fuji: Clarification about R and RW/Rewritable
profiles
>>>
>>>
>>>
>>>
>>>
>>>> Dear Peter, All,
>>>>
>>>> If I correctly understand your analysis, you analyzed the capabilities
>>>> claim from the DVD+R/W *feature(s)*. And in the paragraph which you
quoted
>>>> for "This feature may be present only to represent additional capability >>>> to the
>>>> DVD-ROM Profile. If the Write bit is set to zero, then no additional
>>>> capability is claimed.", is also said eventually "A device may report
this
>>>> feature only when Profile 10h (DVD-ROM) is reported. No additional
>>>> commands or mode parameters are required."
>>>>
>>>> I am working on drives that reports the DVD+R/RW *profile*, not only the >>>> feature. And in the profile definition, the additional commands support
is
>>>> listed as mandatory. ("Drives identifying Profile 001Ah as current shall >>>> support the features listed in Table 221.")
>>>>
>>>> Would it be correct then to say that a DVD-ROM that want to claim only
>>>> recognition of DVD+R/RW but *not* of additional commands has to list
only
>>>> the DVD-ROM profile and the DVD+R/RW feature(s) but *not* list the
>>>> DVD+R/RW profile(s)?
>>>>
>>>> I still don't know actually if this would mean that blank DVD+R/RW media >>>> are recognized or not. As the MMC specification does not make a
>>>> distinction in the support of DVD+R/RW between blank and recorded media, >>>> would it be correct to claim that devices claiming DVD+R/RW support have >>>> to support blank DVD+R/RW also?
>>>>
>>>> Best regards,
>>>>
>>>> David Burg,
>>>> Microsoft.
>>>>
>>>> -----Original Message-----
>>>> From: Peter Van Hove [mailto:Peter at Smart-Projects.net]
>>>> Sent: Monday, October 16, 2006 1:26 PM
>>>> To: David Burg; mtfuji5 at avc-pioneer.com; t10 at t10.org
>>>> Subject: Re: MMC/Mt Fuji: Clarification about R and RW/Rewritable
profiles
>>>>
>>>> Dear David, All,
>>>>
>>>> I hope I'm not completely missing the point but
>>>> for DVD+R/W the way I understand it is the following.
>>>>
>>>> Suppose a DVD-ROM drive doesn't report any of the DVD+ (plus) profiles
>>>> (and
>>>> hence also no features), then a modern drive will likely have no issues
>>>> with
>>>> DVD+R/W discs but will not recognise them as such, only as DVD-ROM discs >>>> and
>>>> blank media will likely not be seen as such.
>>>>
>>>> Suppose a DVD-ROM drive that DOES report the DVD+ profiles then indeed a
>>>> host must still request the relevant features to see if that drive is
able
>>>> to write also in addition to reading the media. Since the ROM drive
can't
>>>> write, the write bit will be set to zero.
>>>> All this means is a "guarantee" that +RW media is properly recognised,
>>>> nothing more.
>>>> MMC says:
>>>> "This feature may be present only to represent additional capability to
>>>> the
>>>> DVD-ROM Profile. If the Write bit is
>>>> set to zero, then no additional capability is claimed."
>>>>
>>>> I understand "then no additional capability is claimed." as compared to
>>>> the
>>>> DVD-ROM profile.
>>>> The DVD-ROM profile's "interesting" feature is the DVD Read feature.
>>>> The DVD read feature does not include the "READ DISC INFORMATION"
command.
>>>>
>>>> In other words, a ROM drive that supports the DVD+ profiles and
features,
>>>> but doesn't support the write bit to one, does no more than a DVD-ROM
>>>> drive
>>>> without the DVD+ profiles and features, EXCEPT maybe that it's a
guarantee
>>>> that DVD+R/W is supported *EVEN* when the booktype is still the original
>>>> booktype, and not the DVD-ROM booktype that is often used for
>>>> compatibility.
>>>>
>>>> I could be wrong, but this is how I understand it.
>>>>
>>>> PS., also from MMC (for the DVD+R feature for instance)
>>>> "If a Drive reports this feature with the Write bit set to one and the
>>>> Current bit set to one, then it shall support the
>>>> commands shown in table ..... "
>>>>
>>>> So only when the write bit is set to one additonal commands are
supported,
>>>> including:
>>>> the "READ DISC INFORMATION" command
>>>>
>>>>
>>>> Best Regards,
>>>> Peter
>>>> -------------------------------------------------------
>>>> Peter Van Hove
>>>> www.Smart-Projects.net
>>>> www.IsoBuster.com
>>>> -------------------------------------------------------
>>>> -------------------------------------------------------
>>>> ----- Original Message -----
>>>> From: "David Burg" <daviburg at windows.microsoft.com>
>>>> To: <mtfuji5 at avc-pioneer.com>
>>>> Cc: <t10 at t10.org>; "Bhanu Gogineni" <bhanu.gogineni at microsoft.com>;
"Ahmed
>>>> Tolba" <ahmed.tolba at microsoft.com>
>>>> Sent: Monday, October 16, 2006 8:10 PM
>>>> Subject: RE: MMC/Mt Fuji: Clarification about R and RW/Rewritable
profiles
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>> * From the T10 Reflector (t10 at t10.org), posted by:
>>>>> * David Burg <daviburg at windows.microsoft.com>
>>>>> *
>>>>> Hello Katata-san,
>>>>>
>>>>> Thank you for your answer. Your analysis is correct, in particular for
CD
>>>>> and DVD dash where the said profile requests write features to be
>>>>> supported. But remains the particularity of the DVD plus command set,
>>>>> where the profile does not request write features to be supported
unless
>>>>> the write bit of the DVD+R/RW feature is one. Still, DVD Read feature
is
>>>>> always mandatory, and this one includes the same READ DISC INFORMATION
>>>>> you
>>>>> mention.
>>>>>
>>>>> Best regards,
>>>>>
>>>>> David Burg.
>>>>>
>>>>> -----Original Message-----
>>>>> From: owner-mtfuji5 at avc-pioneer.com
>>>>> [mailto:owner-mtfuji5 at avc-pioneer.com]
>>>>> On Behalf Of keiji_katata at post.pioneer.co.jp
>>>>> Sent: Sunday, October 15, 2006 11:47 PM
>>>>> To: mtfuji5 at avc-pioneer.com
>>>>> Cc: t10 at t10.org; Bhanu Gogineni; Ahmed Tolba
>>>>> Subject: Re: MMC/Mt Fuji: Clarification about R and RW/Rewritable
>>>>> profiles
>>>>>
>>>>>
>>>>> Hi David,
>>>>>
>>>>> ----- Question -----
>>>>> So the question is: Does reporting R and/or RW/Rewritable profile by a
>>>>> drive
>>>>> mandate that it is capable of recognizing the matching blank R and/or
>>>>> RW/Rewritable profile?
>>>>> -------------------
>>>>> I think it is yes. All commands listed in the Features those are listed >>>>> in
>>>>> the
>>>>> Profile shall work correctly. So for example, CD-R profile requests
>>>>> "Incremental
>>>>> Streaming Writable Feature" and "CD Track at Once Feature". These
>>>>> Features
>>>>> request READ DISC INFORMATION command and READ TRACK INFORMATION
command.
>>>>> Those
>>>>> information must be reported from any condition of the CD-R disc except
>>>>> fatal
>>>>> error condition of the drive. I think Blank condition of CD-R is normal
>>>>> condition of the disc.
>>>>>
>>>>> On the other hand, these Feature request "This Feature identifies a
Drive
>>>>> that
>>>>> is able to write data". Therefore ROM drive shall not report the
>>>>> supporting of
>>>>> there Features. Then ROM drive cannot report CD-R profile.
>>>>>
>>>>> Best regards,
>>>>>
>>>>> Keiji Katata
>>>>> PIONEER CORP.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> David Burg <daviburg at windows.microsoft.com>@avc-pioneer.com on
2006/10/14
>>>>> 14:05:28
>>>>>
>>>>> mtfuji5 at avc-pioneer.com$B$KJV?.$7$F$/$@$5$$(B
>>>>>
>>>>> $BAw?.<T(B: owner-mtfuji5 at avc-pioneer.com
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> $B08 at h(B: <t10 at t10.org>, <mtfuji5 at avc-pioneer.com>
>>>>> cc: Bhanu Gogineni <bhanu.gogineni at microsoft.com>, Ahmed Tolba
>>>>> <ahmed.tolba at microsoft.com>
>>>>> bcc:
>>>>> $B7oL>(B: MMC/Mt Fuji: Clarification about R and RW/Rewritable
profiles
>>>>>
>>>>> Hello,
>>>>>
>>>>> During validation of DVD-ROM devices conformance to the MMC command set
>>>>> through
>>>>> the Windows Vista Logo program and MMCTest tool, we were signaled the
>>>>> possible
>>>>> flaw in either our tool or the specification. Our tool query from the
>>>>> drive the
>>>>> list of profiles supported by the drive, and then exercises each of the
>>>>> profiles. Some ROM drives will also report R and/or RW profiles. Thus
our
>>>>> tool
>>>>> attempts to validate these profiles, and as part of the validation
>>>>> attempts to
>>>>> validate that the drive recognize blank media properly.
>>>>>
>>>>> Yes, blank media. I understand that hardware manufacturers may very
well
>>>>> be
>>>>> reluctant to guarantee this capability on ROM drives. The value of
>>>>> recognizing
>>>>> blank media in a ROM drive that won$B!G(Bt be able to write it is
also
>>>>> questionable.
>>>>> However there are also positives aspects: a ROM drive able to recognize
>>>>> the
>>>>> blank media will not spin un-definitively in attempt to find a track,
it
>>>>> will
>>>>> further be capable to report that the media is blank to the host so
that
>>>>> the
>>>>> host software may report the issue to the user and help him to correct
>>>>> his
>>>>> mistake.
>>>>>
>>>>> Clearly some ROM drives do not support recognizing blank recordable or
>>>>> rewritable media, even sometimes do not recognize recorded recordable
or
>>>>> rewritable media.
>>>>>
>>>>> So the question is: Does reporting R and/or RW/Rewritable profile by a
>>>>> drive
>>>>> mandate that it is capable of recognizing the matching blank R and/or
>>>>> RW/Rewritable profile?
>>>>>
>>>>> Best regards,
>>>>>
>>>>> David Burg,
>>>>> Microsoft Corporation.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> *
>>>>> * For T10 Reflector information, send a message with
>>>>> * 'info t10' (no quotes) in the message body to majordomo at t10.org
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>> *
>>> * For T10 Reflector information, send a message with
>>> * 'info t10' (no quotes) in the message body to majordomo at t10.org
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>>>
>>>
>>>
>>>
>>
>> *
>> * For T10 Reflector information, send a message with
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>>
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