Cps2 - Battery vs infinikeyed

[pixelvsprintdot]

Hi everyone,

Just wanted to get some clarification on the infinikey vs battery subject. Not looking at cost or time or anything other then functionality. Is there any good argument for having a battery over the infinikey installed on your boards ? Like maybe hi score can save or characters unlock over time in some games ?

I feel like the answer is no , but I wanted to see if any of you guys had some insights.

Thank you in advance

 

[evan1]

The battery just supplies power to the RAM that stores the encryption key. No other data is stored.

There isn't much reason to use the battery anymore, unless you wanted to keep the board 100%, absolutely, in it's original state from the factory (minus keeping the original Maxell battery ), as Capcom officially had no provision to run B Boards without a battery. The infinikey just uploads the key to the proper region in memory at every boot up that would otherwise be retained on powerdown if there was a battery, but otherwise, the program roms are unaltered, so the code being executed is 1:1, as if it were still on it's battery.


Back when phoenixing was the only way to revive dead boards, there was an argument for keeping it on the battery as it kept the board unaltered and left the ROMs in their original state. Phoenixing requires you to rewrite the ROMs with a patched set.

 

[pixelvsprintdot]

The battery just supplies power to the RAM that stores the encryption key. No other data is stored.

There isn't much reason to use the battery anymore, unless you wanted to keep the board 100%, absolutely, in it's original state from the factory (minus keeping the original Maxell battery ), as Capcom officially had no provision to run B Boards without a battery. The infinikey just uploads the key to the proper region in memory at every boot up that would otherwise be retained on powerdown if there was a battery, but otherwise, the program roms are unaltered, so the code being executed is 1:1, as if it were still on it's battery.


Back when phoenixing was the only way to revive dead boards, there was an argument for keeping it on the battery as it kept the board unaltered and left the ROMs in their original state. Phoenixing requires you to rewrite the ROMs with a patched set.

So are saved scores and possible unlocks just not a thing on cps2 games ?

 

[evan1]

So are saved scores and possible unlocks just not a thing on cps2 games ?

Yes. The cps2 is unable to save high scores after power down. All possible unlocks are done with a code in game I believe and have to be inputted every time. Stuff like unlocking Akuma at the character select screen in ST.

 

[Nebula]

Some people out there are arguing if inserting/programming the keys every time the board boots is a good thing, and let it does every boot could be probably harmful in long-term (as the original system was not intented to be reprogrammed lots of times during it's lifetime)
I think that's not really true because the internal memory in DL-1525 is in fact a simple RAM that could be written many times with no issues (like any other RAM).
Don't really know about the process of unlocking prior to writting keys, but it would be probably harmless too, even if it's done every time the board boots.

 

[idc]

Hi all, just to point out that during the CPS2 security reverse-engineering project, Eduardo reported that it’s regular SRAM which holds the security data. It’s hidden alongside the 68000 CPU in Capcom’s custom DL-1525 chip.

SRAM is not subject to wear like flash RAM is. It is not harmful to rewrite the security data on every boot.