I still don't get if i.e. is it possible to get a phoenix JPN rom set without bugs? What are the reasons for Oliveira and idc project?
I know this is a little off topic but I want to answer this one. There is no issues getting JPN region games without bugs. The issues come when you have a game in a single region only. Its not impossible though, it just takes longer (I had no issues doing Vh2 and VS2 for example). A lot of the problem with bugs in the first CPS2 phoenix games came from the fact that incorrect and altered phoenix dumps were added into MAME. I did tell them at the time but no one wanted to listen. Then you had people altering them and those got added to MAME also.... There are still incorrect versions in MAME the last time I checked. At one point there was even phoenix fixes with mismatched ROMs that did not need altering, that all came about from people selling fixed ROMs for only altered ROMs rather than the entire program ROM set. The amount of people who have contacted me who have been caught out by this problem is unreal. Seems one of the most effected games from this is SFA.
I never released the phoenix fixes publically and probably never will. They are designed for people with real hardware only.
I'm not sure the reasons for the Oliveira and idc project. To be honest I did not know about it until I looked it up now. Personally I'm against these kind of fixes not showing a logo of an altered game. It seems they also think the games have been altered without knowledge, this is not the case for the phoenix edition fixes I have at least. All changes I have done are known and some are even for the better (like the better program ROM check). As for SSF2T, I have run phoenixed and original games side by side. They run identically, the reason people question this game is due to the way its programmed in relation to the vblank timer.
Changes in the phoenix editions are.....
- altered exception vectors to show errors
- altered video ports (the hardware will not run if you do not do this)
- altered program ROM checksums
- stronger program ROM checks in testmode (Capcom think checking 0x01 byte in every 0xFFF is enough, I don't)
- addition of region screens for a couple of games that did not have them.
- storing the selected region into the end of the EEPROM.
- removal of time locks for games that have them (SFA3 for example)
The truth of the matter is phoenix fixes can be confirmed to be working correctly by a end user more than the original encrypted version given the overly weak testmode ROM check alone. I have seen a lot of corrupted original encrypted ROMs over the years too. I think allot of the issue is people without allot of knowledge still scratch their heads at how one can know what data needs decrypting and what does not. The reality is its really quite simple when you have large data sets and good knowledge of the cpu and knowledge in the way the games were compiled.
Of course CPS3 is a little different given it uses CD and simms so some things can be done in a different way. I have not really been following the progress but it seems it can be quite tricky to update the games sometimes from what I have seen in this thread I'm sure that will change in time though. All I know is how I would do it. I think I have said it before. I would either program one new bios that could load all games. Ie; when you go into the load menu it would list all the games, you would choose one and it would then ask to insert cd after checking required simms were present. I would not want any of this making special CDs for different games, I would make it upload off the original CDs. Of course some people would moan about that given it would have a custom Bios..
