Compatiablity on the MegaSD, I've tried most games on it. Particularly some problem ones (that don't work to well with consoles, emulators, and the like) with unlicensed game, some strange mappers/copyright protections such as Beggar Prince. THese all work just fine.
There is still some work to get some of the Mega/Sega CD games to work, or improve on them as some have some bugs IIRC, dound cuts out, or other graphical issues.
Is there any particular games which you can remember? I'd like to look closer on them using mega-ed.
As far as i can see most of modern MCD cores/emulators uses simplified Mega-CD implementation. During MCD research i did made small test tool for check real hardware behaviours, because sega docs isn't detailed enough for building accurate core. If you ran this tool on Mega-SD or with emulators you will see that almost all tests fails. Checking how it really works probably taked largest part of project time.
Link to the cd test tool for anyone who want to check it: https://github.com/krikzz/MEGA-PRO/tree/master/mcd-verificator
Do not forget to backup your saves before than run it.
Oh ya there is currently an issue with games with large size save files apparently on some systems. But that is something they are promising to fix in a later firmware update.... Shing FOrce CD is apparenlty one of these.
Thanks again for the reply. I am using regular SRAM ( which is more easy to handle at code ) not EEPROM. For test, If I cut some levels to down game size to up to 32Mb, I get the Everdrive working with SRAM. About SSF header this was done in older revisions of the Hack, but some emulators remaps banks 0 when I try to access SRAM. Some emulators (Blastem to be more precise) devs only added support to this ROM hack, after I have assigned a custom serial number to game and removed the SSF header, and GPGX fails to run if SSF header is found.
I can force SSF mapper for your game, but carts with one time programmable fpga like x5 and x3 still not be able to support sram in way how you using it. May be you could include simple check to detect what type of mapper used and then use supported banck switching model?
Most of the fighting team games have copy protection on them. Some of the Piko stuff has copy protection on it too...
There are supposedly packs that Fighting Team sold that removed the copy protection issue. ANd some hackers have remove copy proteciton from some of the games (Fighting Team and Piko)..
Alternatively there are possibly stuff from the stoneagegamer that has the copy protection already removed, but I haven't tested those in emulators to check for sure.
Obviously there was also Pier Solar which had its own issues, but you have shown you have included that in your compatiblity.
Generally speaking there is no issues with any piko roms buyable thorugh Steam.
As for the CD games one of the fighting games I can't remember which has issues... ANd I think Shadowrun CD is said ot have issues... Of course some of this might have to do with MegaSG issues as well, but I don't have actual sega original hardware to test on. But I think there is a list of issues up on the internet somewhere, possibly through the terra onion forums.
A few years ago, some older Everdrives were criticized for having insufficient voltage translation between 3V and 5V parts (although the situation was probably not as bad as it was first given the impression of). The Mega Everdrive X7 is the last Everdrive still in production that seemingly doesn't have sufficient level translation for all control, data and address lines (the X5 and X3 do though). From pictures it looks like the Pro has this though, so the criticism will probably be history with the release of the Mega Everdrive Pro.
So I'm gonna assume this probably isn't an issue for Terraonion, and Pro as far as things go. According to them they were very careful to keep the voltages within the margins of safety. It draws less then the Virtua Racing cart.
