Sega Saturn cp talk

[themabus]

anyway, aren't we just extracting the printed ring text on the CD in bytes and turning it back into readable ASCII text? because both texts are identical:

yeah, that's what we do

maybe it's not there, maybe CAV is used only because it's easier to write logo this way
but many people talked about it being logo.
so i want to be sure if we can not draw it - it's ok, but let's check and see.
in a few days we will know, i think

i recalculated sectors per track, and it looks pretty close to CLV. on Saturn logo takes ~3mm (height)
it's about 2..3 sectors per track difference @CLV from top / bottom of logo. for 1400 tracks it's not that bad, i guess.
i'll make circ encoder and i want to to try to draw some cubes and rays and such on cd firs
if it's possible, maybe logo is too.

edit:
oh, sonic's logo start at the same MSF, where ChuChu Rocket, when leading sectors are removed.
and my rocket dump was desynchronized in middle, so thanks. if i can draw those cubes i'll try dc 1st, because it's closer to centre - can do faster.

[themabus]

it's too dark to take good photo today, but i pretty much have it on 700mb cd-rw

it's distorted, but not as bad as i've thought it would be
it's on 1st try, after probing cd for characteristics with rays
so very possible to improve
tho i went through cdfreaks again and pinchy's page and don't expect it to boot now,
but it was fun

i'll post tools soon

edit:
better picture

[Jackal]

And why don't you expect it to boot?

[p_star]

Amazing !!!

[themabus]

thanks, p_star!

it would be too simple...
on those forums ther's at least two people, who knew how this ring is made: Bexster/RPS (i think it's same person) @cdfreaks and HI_Ricky @segaxtreme/assemblergames.
they would have figured it out, i guess.
only way i can now imagine this to pass is if saturn rotates cd at some speed and checks laser wave, e.g. time for how long ther's short/long waves from pit/land blocks assambling logo pattern. but if it does something more - it would not. and i think it does more. pinchy said his cds pass all checks except the last one. and he's very determined it's before ring, maybe it is gap, like you said, after all. like absence of efm in there.
but anyway i won't give up on this until i try 650mb cd with corrected MSF/subchannel, skipped sectors before ring and ring done in several possible ways (scaled/padded etc.)

here i've redone 1st of those programs:
http://www.mediafire.com/?6zwrdyuz9pt
it interleaves/deinterleaves binary data.

i hope to do rest soon.

[iR0b0t]

what is the difference in burning it on CD-650 or CD-700 ?
pit/land blocks must be of same size if you burning data on this media.

it would interest me, can Sega Saturn read CD-RW's properly? not that you waste your time with CD-RW's

[themabus]

track pitch is different: ~1600nm on 650; ~1480nm on 700mb cd.
so ther's more 'tracks' (spiral revolutions) on 700. this makes all data compressed.
if logo is made on the same number of tracks it would be more narrow,
positioned @the same LBA as on 650mb cd, physically, on the surface, it will end up closer to the center .
assuming that properties of this area are verified, and we strive to simulate them,
ther's too much uncertainty with 700mb imho.
saturn will read RWs after laser is adjusted. on factory settings they wouldn't even spin up.

[iR0b0t]

You've right with track pitch, and I understand your thought and intentions what concerns the logo zone. You believe also the hardware would read the discs, independent of the contents, at exactly logo ring position!? Indeed, this would be crazy!

I have seen that Saturn discs have 2 rings (inner and outer). Or is this inner ring simply the lead-in area?

[themabus]

it might, the thing is - i don't know , closer it is to original the better

honestly, i haven't noticed, but yeah, looks like ring.
it's d ~44 mm..~46 mm for 'inner buffer zone' and ~46 mm..~50 mm for lead in, i think.
but what makes this thin stripe, i don't know. maybe you can compare it with other pressed cds - pc, audio... (better older)?
i only have those few from saturn atm.

edit:
got my saturn now, tried swapping and it can be done so, that only outer part from the original cd is read.
whatever there is @center, it doesn't matter.

[themabus]

ther's another guy: ProgrammingAce @SegaKatana forum
the site is dead now, so i'll repost here, what he wrote:

ProgrammingAce          Post subject:
Posted: Sat Apr 21, 2007 12:12 am
Joined: Thu Jul 20, 2006 1:14 am
Posts: 14        

Grr... my RSS feed here was damaged (i forgot to update, even though mark specifically warned me).

I know quite a bit about copy protections (and saturn specifically). I can tell you that not only is it possible to burned self booting Saturn games, but that it has already been done.

It looks like you're on the right track. If you have any questions, let me know.

ProgrammingAce          Post subject:
Posted: Sat Apr 21, 2007 12:53 am
Joined: Thu Jul 20, 2006 1:14 am
Posts: 14        

Alright, to be a bit more helpful i read through what pinchy said on the cd forums.

Although they're arrogant, they're also right. The pre-ring data is irrelevant, or to be more accurate, non existant. The CD-ROM drive in the saturn isn't any more advanced then what you use in your PC. If you can't force a drive to do a raw read of the sectors, chances are they're no good.

Quote:
I tried to test the counter that is supposed to increment when reading actaul ring data by moving it down to the pre ring area but it still didnt increment.


This confuses me. The check is hard coded to the address location. You're missing the cause and effect. The seek doesn't start the check, the check is a result of the copy protection function.

Save the cheerleader, save the world.

ProgrammingAce          Post subject:
Posted: Fri Apr 27, 2007 5:00 am
Joined: Thu Jul 20, 2006 1:14 am
Posts: 14        

-=FamilyGuy=- wrote:

I noticed that the data seems to be audio, and I don't think it as something to do with any knid of refraction like some are saying .. it makes no sense.

The ring, to me, looks like this : weird sector + a8 59 pattern + weird sectors


The ring data is audio, it's a tone.

The weird sectors are markers, not readable data. Reproducing them would be futile (if even possible without stamping equipment).

it's about the same what Bexster/RPS wrote @cdfreaks

edit:
here, he says more @gamerhistory forum
http://gamerhistory.com/forum/viewtopic.php?t=661