This question is actually more generic than this sub-forum since the OS doesn't matter but it appears close enough.
I was thinking about how emulators work and the many components present in a game system, specifically the PS2. One thing I noticed is that emulators seem to lack copy protection and allow you to use ISOs rather than the original discs. After doing some research on how the PS2's copy protection works it looked as if some of these protection mechanisms can't be removed and yet clearly they have been removed or bypassed somehow. How is this done?
I mean, with the emulator being pure software and all it is clearly possible for them to be removed, but I expect some of them are software checks in the BIOS and some games have copy protection in their code as well. So, how is this dealt with?
copy protection on the PS2 was done with coatings on the dvds. you can't emulate looking for something physically on a disc
Yes, that was one protection mechanism that I read about. But isn't the BIOS expecting that data? If it is then it must either be replicated or the BIOS altered. Or is it all done with dedicated hardware whenever a disc is inserted and you simply don't emulate it?
If there is documentation somewhere that explains exactly how PCSX2 works in detail, including this question of mine, then that would be even better as I am quite curious as to how it all works. I have been considering writing a NES emulator for a while in fact, which I may well do after this research.
This part of PCSX2 was written ages ago but I think the whole copy protection consists of a
magic key check that the PS2 DVD drive does on the disk.
We emulate the drive anyway and simply patch in a good key, as far as I know.
Magic key, region lock and probably other things. The checking for them can't be used. Also making an iso doesn't copy them. Or at least that is what i've been told. They are Sonys proprietary property. Emulators cannot use proprietary properties. This was ruled in a court some years ago. The only thing else i know is a mod chip on the actual hardware told the system that all the copy protection was there.
11-24-2012, 07:57 AM
(This post was last modified: 11-24-2012, 07:59 AM by Amak.)
Arg, damn Firefox and flash are fighting.
I think this works either like Xbox softmods or 360 firmware hacks. Either the protection is bypassed completely or an expected response is always sent.
Thanks for the replies. I would prefer to have all the technical details so that I may understand exactly how it works, but perhaps that requires too much prerequisite knowledge? Or simply isn't readily available. In any case this is sufficient for now, I will research it more another day, probably after I have learned more about emulation in general.
I find it amusing that the copy protection could simply not be emulated but is anyway for completeness.
There is a disc identifier on original ps2 discs which cannot be copied, when you put the disc in, this is copied to memory and used to identify it as a real disc, as soon as you hit the eject button this gets wiped from memory, this is why slide cards and flip lids work as a way of getting around the protection (swap magic). This special data can only be pressed and not copied, which is why backups do not work without the swap method.