What's new

KalessinDB

Grand Master
Joined
Jul 22, 2015
Messages
1,224
Reaction score
894
Location
Rochester, New York
Something occurred to me in light of the breakthrough that is key writing on the CPS2 multi -

Is there any code difference in running the games with the SuperBIOS? Either Custom or Standard SH2? That is to say, is this more akin to Avalaunch/Phoenix roms, or to 100% original code?

I'm nowhere near competitive levels on these games, I won't be submitting high scores anywhere, it's really just idle curiosity, especially since I now have a Big Blue that I'm going to be stuffing all my Darksoft Capcom multis into.

Thanks!
 
long time ago since I looked into it, but IIRC;
standard BIOS runs unmodified code and custom BIOS runs encrypted code.

And to avoid any confusion, the BIOS installed on genuine carts is the custom BIOS ;)
So you only have standard BIOS is you actually changed it.
 
Well I'm pretty sure that mine's the custom, so very cool. Thanks for the update
 
The difference is that in the custom version, the processor has a small section embedded that decrypts the instructions "on-the-fly" so that they can be processed. The decryption is done in the processor itself. If we use a standard SH2 those instructions must reach the processor already decrypted. The decryption process in the custom CPU version is completely transparent and adds no delay at all so we can safely say that both versions are identical and execute exactly the same code in the same conditions.
 
Back
Top