EEPROM saving unsupported.

[Damedade]

Saving for these games is unsupported.

Barkley: Shut Up and Jam! 2 (EEPROM)
Blockbuster World Videogame Championship II (NBA Jam T.E. portion) (EEPROM)
Brian Lara/Shane Warne Cricket (Europe/Australia exclusive title) (EEPROM)
College Slam (EEPROM)
Evander "Real Deal" Holyfield Boxing (EEPROM)
Frank Thomas Big Hurt Baseball (EEPROM)
Greatest Heavyweights of the Ring (EEPROM)
Mega Man: The Wily Wars (Europe uses EEPROM, Japanese release uses SRAM)
Micro Machines '96 (Europe exclusive title) (EEPROM)
Micro Machines 2 (Europe exclusive title) (EEPROM)
Micro Machines Military (Europe exclusive title) (EEPROM)
NBA Jam (EEPROM)
NBA Jam Tournament Edition (EEPROM)
NFL Quarterback Club (EEPROM)
NFL Quarterback Club '96 (EEPROM)
NHLPA Hockey '93 (EEPROM)
Rings of Power (EEPROM)
Sports Talk Baseball (EEPROM)
Unnecessary Roughness '95 (EEPROM)
Wonder Boy in Monster World (EEPROM)

[ogamespec]

Any suggestions for implementation?

[birdybro]

Any suggestions for implementation?

sorgelig implemented this in the MiSTer port initially here:

MiSTer-devel/MegaDrive_MiSTer@e01312a

Check later updates to the module here:

https://github.com/MiSTer-devel/MegaDrive_MiSTer/commits/main/rtl/EEPROM_24CXX.sv

We detect the header and set a flag for this kind of thing. The EEPROM modules used in the MiSTer project are usually state machines with a few extra steps mimicing the datasheet or other RE research. Krikzz did a lot of initial research on how all these eeprom work here --> https://krikzz.com/pub/support/everdrive-md/v2/gen_eeprom.pdf - I think the vast majority of this still holds accurate today if I'm not mistaken. You can also see how ekeeke handles it in genesis-plus-gx (https://github.com/ekeeke/Genesis-Plus-GX/tree/master/core/cart_hw) since his handling of it accurate afaik. It's in the md_cart and eeprom_xxx files