Searched and couldn’t find anything. (Maybe my search skills suck?)
For example, if I were to play SF all six buttons would light up. If I switched games to Galaga, then only one button would light up. I think this would be handy, especially on boxes that have a ton of games on them.
There would have to be a way of accessing available buttons and I don’t know if any MAME emulators let you do this. Any ideas?