Great work mr D
I don’t suppose you’re going to mass produces them?
Probably not ^_^; the component cost for one of these guys comes to something like $18-$25. There's no way I could get it that much cheaper than Everdrives and so on, and those carts support savegames and mappers and things. (My cart won't ever play Pier Solar or Super Street Fighter II The New Challengers since they're too big.) I don't know how much cart shells cost. It would probably be easier for me to buy fifty or a hundred 'replacement cart shells' from some retro shop, put GRs inside them and that's that (except for the SD card slot...).
I'm not sure what I'm going to do when I get the cart working. It's more of a portfolio piece than anything. I was thinking of putting it all under agpl3 license so anybody can do what they want with it as long as they give out the source. I'm not too fussed about chinese clones, since these things already exist, and considering I'm getting it made in China that horse has already bolted.
When they're finished I'll see how much everything would be.