Is there an ds emulator and roms that work?
I use the R4 emulator; it’s really cool. The updated software lets you cheat in most ROMs, though the words are in Mandarin, which means you generally don’t know what cheats you’re using unless you know Mandarin. The chip costs about $700NTD ($20USD) here in Taiwan; I don’t know if you can get them elsewhere and what they cost. But it takes 2gb microSD cards that each fit around 50 games on them, so I just keep a little rubberized packet connected to the little eyehole for the strap at the top near the cartridge intake to hold a half-dozen microSD cards with all my games on them. Overall, it costs about $60 to do it all, because of all the SD cards you need to buy to hold all your ROMs. My DS is a limited edition Zelda version I got in the USA two years ago and the Chinese R4 works fine in it. Being able to cheat in Conta 4…vital…