Reverse Engineering the PSX Copy Protection (Wobble Groove)

[Davide_G]

I can't wait to be able to use the black CDs I bought!
https://www.nierle.com/en/article/1001/ ... ieces.html

[Shadow]

Try a PU-7 or PU-8 board with the analog servos and adjust the laser power slightly since CD-R's require more gain

[kylemn]

Hello gentlemen. Following the discussion about disk security here. I want to help in some way, but I don't have all the methods, but I have an important one. I can manufacture it in my industry, on pressing machines. However, I only have the machines. I receive the stampers (master disc for pressing machine) from someone in the USA. I send the DDP (game or music image) ready for them to manufacture the stamper and send it to me to reproduce the discs in polycarbonate and bla bla bla. Should all ATIP or TE information be inserted into the stamper? Can they be inserted into an iso previously? How would this be done? any software? Does it have to be done when creating the Stamper? Do you know what the process of creating a Stamper is like? What software are you using? If you discover this, we can be partners in these experiences.
You can contact me whenever you want.

[david4599]

Hey, that's quite nice that you are in this industry!

The idea for replicating the copy protection was explained quickly in a youtube comment of a former Datel engineer that I mentioned earlier in this thread.
It's not something that we can insert into an iso file, it's basically made the same way as the ATIP but with a different modulation and data.

At the glass mastering step, we would "simply" need to replace the ATIP generating machine by a modchip that will send or not the 22kHz signal to the disc depending on the SCEx data.
This way, the pregroove will just be a 22kHz amplitude-modulated signal of the 250bit/s SCEx serial data instead of the ATIP.

I'm not totally sure but I think there are actually 2 ways to do it. Either by a modulated pregroove like the ATIP or directly the pits/lands that are shifted radially without any pregroove.
But how easy would it be to create a CD-ROM stamper with oscillating pregroove (usually for CD-R/RW process) or oscillating pits/lands?

However, from what I understand, you just receive the already-made stampers, so is it something that you would be able to do? Do you even have access to the ATIP and pits/lands generating machines?

[cunningfellow]

Hi David,

Fantastic work.

I think you might be referring to me when you said "was done 20 years ago on a private forum" I am guessing it was Mr Lau that told you those two decade old stories.

The method was to increase the disc rotational speed so that the 20Khz wobble became a 60Khz wobble.

If you are actually able to boot to a game and play then you have done better than me. I was able to inject the wobble to make the SCEE string and get the CD Controller into data mode. Other things happened in my life that made me not pursue it further. I'd done what I thought was the hardest part of the challenge so I was happy with myself even if I didn't end up with a 100% useful result.

I may still have the hardware sitting in some cardboard boxes somewhere. The burner was a HP4020i (rebrand of philips CDD2000 I think). I did not modify the firmware at all. I am not smart enough to do that kind of thing. It just had blue wires and lifted pins so I could change the rate at which the EFM data was being spat out.

If those forums got archived anywhere you should search for the string "Violently Colliding Peramelidae 2"

[david4599]

Hi, thanks!

That's great to get more information on the origins of the project!
I don't know Mr Lau but I will check with the guy that told me the story.

I guessed that increasing the disc speed was your solution too.
60kHz seems a bit extreme to me but at least the original wobble is not an issue anymore.

I'm a bit worried to go far beyond the supported speeds knowing that the disc may leave its support. Also the spindle hubs are old and some of them come to pieces with time. Reading game data in 2x mode would be scary at this speed.