Something like that?
http://www.ebay.com/itm/GALAXIAN-High-Score-Save-Kit-/281601194272
I wanted to buy one but $45 + $27 shipping is a bit too much for me these days.
yes, something like that, but no nvram. a nvram has the disadvantage that there is a battery inside (the dallas chips are already old, so i do not know how long the battery will last)
i use a serial eerprom.(no batteries anymore). the only limitation on a serial eeprom are about 1 million write cycles.
and there are software dips included. that means there is a menu at startup where you can change your settings.
and all the "standard" routines e.g. free play attract mode...
@andre: i didn't plan a multi kit - only for galaxian and uploading highscores would be there of course
edit: the online option will be ALWAYS available on ALL kits i will do
edit2; okay, except the bumpNJump saveKit (because the code is decrypted and it was a pain in the ass already to decrypt my own code for saving and loading highscores) - maybe someday if there is a loooot of time
