Does anyone here have experience with 2-wire serial EPROMs? I'm looking for one that could easily interface with the 9901. While I could probably squeak by with 128 bytes, I would certainly not be opposed to larger sizes up to 256K. What I'd like to do is connect the clock and serial data pins to the 9901, using two unused pins. I'd then use the serial eeprom to store configuration information for the Geneve and its devices.
20-odd years ago Jim S. had interfaced a serial eprom to the Geneve to provide Cecure a hardware-based copy protection. Thus I know a 2-wire device can be implemented, I just don't know what is available today that might work well for this application.