Command set proposal for Hybrid disc

keiji_katata at keiji_katata at
Mon Aug 8 20:14:09 PDT 2005

* From the T10 Reflector (t10 at, posted by:
* keiji_katata at

Hi Ai san,

I basically agree to use Profile code to show the hybrid disc structure.
Therefore the table of "1-2. Format-layer type code" should have "Profile
0050h: HD DVD-ROM".

Generating UNIT ATTENTION and New Media Event also is good. But I think
host application should be able to control the UNIT ATTENTION and New Media
Event generation. Therefore "2-1. START STOP UNIT command" function could
be as follows;

      Layer Destination LoEj  Start Power       Operation to
No          Format-layer#                 Condition   be Performed
1     0           0     0     0     0           Stop the disc
2     0           0     0     1     0           Start the disc
3     0           0     1     0     0           Eject the disc
4     0           0     1     1     0           Load the disc
5     1           N     0     1     0           Change the Format-layer
6     1           N     1     1     0           Change the Format-layer
7     0           0     x     x     1h - Fh     Power condition change

Number 5 is the additional function. In this case, drive shall change the
current profile to the specified Format-layer. Drive shall generate
Operational Change Event with Operational Event field "2h Logical unit may
have changed Operational State", Operation Request/Report field "1h Feature
Change". Drive shall not generate UNIT ATTENTION and New Media Event.

The host software that can handle two different Physical Format Layers can
       handle both layers at the same time.

Best regards,

Keiji Katata

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

More information about the T10 mailing list