Ok. Sega MD/Genesis EEPROM save support is done.
I had a bit of trouble with the Acclaim Type 2 and Codemasters carts.
The Acclaim Type 2 carts use a PAL chip to interface with the 24XXX EEPROM. I got the Acclaim Type 2 working with a tip from Eke (eke-eke) on the PAL initialization for the EEPROM. I had completely missed it in my logic analyzer logs.
Codemasters carts also use a PAL chip but there's no initialization needed for the EEPROM. The Codemasters carts do require the CLK signal. I couldn't get the EEPROM responding to the commands until I bridged the CLK to /C_CE (the MD shield doesn't have a CLK pin). This is similar to the Codemasters GG/SMS carts which also need the CLK. When I was working on the Retrode code, I found out about the CLK problem with Codemasters carts.
I'll clean up the code and get it submitted to sanni. I also modified the SRAM code to handle all the types of SRAM along with the carts that have bad header save data.
BTW, years ago, Eke (eke-eke) posted some PDFs with Sega EEPROM documentation. Some of the info in the documents is incorrect/outdated. Refer to his Genesis Gens GX source code for the most up-to-date EEPROM info.