Some technical questions ...

[MagnAyato]

Hi,

I am looking for answers to technical questions about Compact Disc technology.
I searched on the Net but I did not find clear answers.
I know that here there are people both passionate and competent in this area.
I would like to have the opportunity to ask these questions to the community.
There is a strong chance that people can help me.
At the same time it could be of interest to other people.

Can I ask my questions ?

[wiggy2k]

ask away. i might learn something too

[MagnAyato]

Thanks !

So here is the first one :

About physical sector distribution on compact disc :

On “Upgrading and repairing PC S” book (chapter 11 page 525) author says :

“On a disc that can hold a total of 74 minutes of information, that results in a maximum of 333,000sectors.”

Are those 333,000 sectors included in the Information Area or Program Area ?

Assuming :

Information area : from start of lead in through end of lead out.

Program Area : from end of lead in through start of lead out.


Thanks for help.

[MagnAyato]

Meaning of ATIP start of lead in

When reading parameters from different brand of CD recorable disc, I notice
it never have the same ATIP start of lead in value.

For example :

ATIP info from disk:
Indicated writing power: 4
Disk Is not unrestricted
Disk Is not erasable
Disk sub type: Medium Type A, high Beta category (A+) (3)
ATIP start of lead in: -11849 (97:24/01)
ATIP start of lead out: 359847 (79:59/72)
Disk type: Long strategy type (Cyanine, AZO or similar)
Manuf. index: 25
Manufacturer: Taiyo Yuden Company Limited

Here ATIP start of lead in = -11849LBA or 97:24:01 MSF.
So size of Lead in is 11849 sectors because Lead in spread from MSF start 97:24:01 to MSF end 00:00:00.

But the standard says that the size of a standard lead in is 14.65Mb/7500 sectors.

https://books.google.fr/books?id=Hs23Aa … mp;f=false

So what is true ?

[MagnaAyato]

About Q Mode 5 Lead out subchannel with point D1 value

I need a little precision about “Q Mode 5 Lead out sub channel with point D1 value”.
It seems that in lead out, such sub channel could exist in the lead out area.

The 72 data bits should be like below :

8 bits for track number (fixed, must be AAh=Lead-out)
8 bits for point (D1h, Identifies a multi session lead-out)
24 bits : I do not know …
8 bits: I do not know …
24 bits : I do not know …

I assume that Mode 5 subs are present for multi session discs (that mean for me [2,N] (N>=2) sessions).

I had crawled everywhere, even on ECMA and MMC but no information about it …

Thanks for all the help you could provide.

[iR0b0t]

“On a disc that can hold a total of 74 minutes of information, that results in a maximum of 333,000sectors.”

>> Program Area : from end of lead in through start of lead out.

But this number can vary between CD pressing factories. Besides of that, you can extend this number by over-burning the CD into lead-out sectors, you don't really need the entire lead-out section to close the disc or sessions.

[MagnAyato]

Than you very much iR0b0t .
Your reply solves 1 of my 3 questions

[MagnAyato]

About CLoneCD CCD file :

In the session section of CCD file there are always two keywords “PreGapMode” and “PreGapSubC” like below :

[Session 1]
PreGapMode=N
PreGapSubC=M

where N is in [0,1,2]
where M is in [0,1]

What is the meaning of those keywords and values ?

Thanks for help.

[iR0b0t]

“PreGapMode” = [0,1,2]
most likelly the data type mode of the track's pregap: Mode 1, 2 or 0 (all three valid values for a data track)

“PreGapSubC” = [0,1]
track subchannels, allow or disallow (enabled or disabled)

[MagnAyato]

Question about CloneCD CCD file Disc section

[Disc]
TocEntries=18
Sessions=1
DataTracksScrambled=0
CDTextLength=810
CATALOG=5479154328763

What means DataTracksScrambled and what values could be set ?



Thanks for help.