I've been doing a bit of reading about the 7800 and here's my thoughts on the SD cart for it...
- 1MB battery backed SRAM allowing for any combination of RAM / ROM mapping upto 1MB in total (covers all known games to my knowledge).
- Support for the high score cartridge saves (which will be persisted to SD card also).
- Ability to load any ROM from SD and play it, much the same as the LynxSD (ie. programmed every time, not flashed).
- Built in POKEY via hardware simulation (probably MikeJ's POKEY hardware from Asteroids Deluxe as a starting point).
- Support for all 2600 and 7800 mappers (hopefully programmable mapper hardware such that any different mapping scheme can be setup).
This doesn't seem too unreasonable or even too complex looking into it a little further. More complex than NGPC but simpler then Jag.
This isn't going to happen for some time, so don't get excited or anything, just getting a feel of what is wanted and how many people are likely to want it.
Any further thoughts / ideas, please say.