By hooking up a bunch of hardware to the STV cartridge and hacking away at the program a bit Peter Wilhelmsen, Morten Shearman Kirkegaard and myself managed to get a bunch of decrypted data out of Decathlete. Morten managed to figure out the encryption / compression based on that, Samuel Neves then helped work out a few details to simplify things etc. and I got their code running in MAME.
Not marked it as working yet because performance is awful (STV driver issue) but the game is playable, protection / encryption figured out. I'll do a full write up later.
The same type of protection is used by the following games, provided by the listed protection chips
315-5838 - Decathlete (ST-V)
317-0229 - Dead or Alive (Model 2A) & Name Club / Name Club Ver 2 (ST-V) (NOT NAME CLUB 3)
317-0230 - Winnie The Pooh Vol 2 / Winnie The Pooh Vol 3 (ST-V)
317-0231 - Print Club Love Love / Print Club Love Love Ver 2 (ST-V)
Name Club / Name Club 2 have a large amount of compressed data, so it *might* be possible to figure those out without access to the actual chip (and as the chip label is the same as DOA, that should be the same encryption) They encrypt the data used for the printer, so it isn't obvious onscreen that they're protected while Dead or Alive encrypts a single short string in the dumbest possible use of the chip ever from a protection point of view.
317-0230 (Winnie The Pooh) and 317-0231 (Print Club Love Love) only seem to provide us with a small amount of data, a block of SH2 code used on startup, so it's likely we'll need access to the chips to get the proper algorithm.
AFAIK these are all DU dumps, so it shouldn't be an issue to get the carts in question to Peter. Since I'm not allowed to email Smit, I'm therefore using this place to put in the request, or at least a request to have them on standby.
|
Previous 
Index 
Next 
Flat 
Decathlete progress + Peter / Morten might need some of the carts the DU dumped for the protection chips
Reply
