READ DISC STRUCTURE command

Takaharu Ai ai.takaharu at jp.panasonic.com
Tue Oct 4 05:36:11 PDT 2005


* From the T10 Reflector (t10 at t10.org), posted by:
* Takaharu Ai <ai.takaharu at jp.panasonic.com>
*
Hello Kohda-san,

Thank you very much for your information.

I believe the Layer Number field for Format code FFh is meaningless, but
I agree to confirm this issue in the next Mt.Fuji meeting.


Best regards,

Harry Ai
VBU
Panasonic AVC Networks Company
Matsushita/Panasonic
Osaka, Japan


---------------- Start of the original message ----------------
>From: takeshi_kohda at post.pioneer.co.jp
>To: Takaharu Ai <ai.takaharu at jp.panasonic.com>, mtfuji5 at avc-pioneer.com
>Cc: T10 <T10 at t10.org>
>Date: Tue, 04 Oct 2005 19:45:53 +0900
>Subject: Re: READ DISC STRUCTURE command
>
> Dear Ai-san,
> 
> My previous comment was not correct.
> The following sentence is described in READ DISC STRUCTURE command on page
> 582. (Fuji6 rev0.95)
> 
> "Note: This DISC STRUCTURE is generated by the logical unit rather than
> read from the medium."
> 
> And the Format Code (FFh) works regardless of existence of a medium in the
> drive.
> So when a medium is not mounted in the drive, the Layer Number field is
> definitely meaningless as you said.
> In this sense, even if a medium is mounted in the drive, the Layer Number
> field of Format Code FFh may or may not work.
> I would like to confirm it in the next Mt. Fuji meeting.
> 
> Best regards,
> ---
> Takeshi Kohda
> 
> 
> 
> 
> 2005/10/03 15:35, takeshi_kohda at post.pioneer.co.jp wrote:
> >
> > Dear Harry-san,
> >
> > > Also, Layer Number field in CDB for FFh is meaningless.
> >
> > I think the Layer Number field is meaningful if the Disc Structures prese
> > nt
> > in each layer is different.
> > For example, a DVD OTP disc does not contain Physical Format Information
> > on
> > Layer 1 because there is no CDZ.
> > But DVD PTP disc contains it on Layer 1 because CDZ is there.
> > The list of returned structure may be different between Layer 0 and Layer
> > 1.
> >
> > The change of the "Layer Number" field to the "Reserved" field is technic
> > al
> > change and therefore we need confirmation among members.
> >
> > Best regards,
> > ---
> > Takeshi Kohda
> >
> > 2005/09/30 17:16, Takaharu Ai <ai.takaharu at jp.panasonic.com> wrote:
> > >
> > > Hello Mt.Fuji members and MMC members,
> > >
> > >
> > > We find one small problem on Mt.Fuji6 Rev 0.95.
> > >
> > > The problem is on READ DISC STRUCTURE command with Format code=FFh.
> > > The current definition is;
> > >
> > >     The Format Code value of C0h through FFh are used to return media
> > >     independent information. Regardless of the Sub-command field value
> > >     in CDB, the same information is returned to the host.
> > >
> > > But the following contents of the Format Code value of FFh varies
> > > according to Sub-command.
> > >   - DISC STRUCTURE Data Length
> > >   - Format Codes applicable to the specified Sub-command
> > > Also, Layer Number field in CDB for FFh is meaningless.
> > >
> > >
> > > So, we think the definition should be;
> > >
> > >     The Format Code value of C0h through FEh are used to return media
> > >     independent information. Regardless of the Sub-command field value
> > >     in CDB, the same information is returned to the host.
> > >
> > >     For Format Code value of FFh, supported Format Codes for the
> > >     specific Sub-command and their length shall be returned according t
> > o
> > >     the Subcommand field value in CDB.
> > >
> > > And the Layer Number field for Format Code FFh should be Reserved.
> > >
> > >
> > > Harry Ai
> > > MSDC
> > > Panasonic AVC Networks Company
> > > Matsushita/Panasonic
> > > Osaka, Japan
> > >
> > >
> > >
> >
> >

----------------- End of the original message -----------------



*
* For T10 Reflector information, send a message with
* 'info t10' (no quotes) in the message body to majordomo at t10.org





More information about the T10 mailing list