A friend is making some superb hardware for a favourite vintage computer of mine and he's inspired me to get out the soldering iron after quite a hiatus. Apparently a PI Pico2 makes quite the ROM emulator.
Pictured left is the prototype, now sadly deceased - RIP Pico2 - your brave sacrifice will be be long remembered, and right is the product of that successful test. It's currently loaded with a menu and all the Inufuto games.
I'll work on the software side of things as it's a fairly involved process at the moment, though nothing a relatively enthusiastic retro fiend couldn't handle. Oh go on then. It involves compiling a little pico program, and including in said program a ROM image. Multi cart functionality compatible with M5-Multi is enabled so you can have a number of rom images on there, selectable at run time.
This cart would be useful to anyone writing new software who want to test it on real hardware, or someone less worried about the convenience of having all the games 'just there' and working like they would with the M5-Multi.
Please ignore the reset switch pads over there on the left. Adding a switch and pressing it will damage your M5. Ask me how I know. RIP M5 - your brave sac... ahem.
I have a limited number of boards available and if you would like to buy one they'll be available on Sell My Retro along with their older brother soon.