Questions about N64 memory cards and Gameboys

[HyperHacker]

For a while now, I've been wanting to make a rewriteable Game Boy cart, but didn't have any SRAM/EEPROM/etc to use. (No, I don't need suggestions on where to buy it. Just money. ) Then a friend of mine gave me a hell of an idea. N64 memory cards are rewriteable, more than big enough for most GB games, and essentially useless. (On the off chance I do play N64, I never actually use the damn thing.) I could remove the chip from it! Problem, though - AFAIK, they're EEPROM and I have nothing to program it with. That's when I got an even better idea. Why take the memory card apart when I could just build an adaptor? Take the port off an old controller and use the entire card as my ROM! I could even use the N64 to rewrite it.

So, this has left me with a lot of questions:

1) What kind of memory do N64 memory cards use, and how fast is it?
2) What's the pinout of the memory card port (the side with the solder) on an official N64 controller?
3) Is there any unlocking procedure required to read it? (For writing, I'll have to hack the code into an existing game anyway, so I'll just use its memory card functions.)
4) Can an N64 game write to the memory card in raw mode, ignoring any headers/filesystems/etc? (That is, if I uploaded a GB ROM to the game's memory, could I write it straight to the memory card and actually run it on the GB?)
5) How much power do the memory cards use?
6) How much space is available on an official memory card?
7) What code would I use to write to the memory card this way?

If there's anything else I should know, of course, be sure to point it out. Also, I should mention that I'm pretty sure I don't have an official memory card (but can probably pick one up), but I do have a 'Super Memory Card 2001', IIRC. (I think that's what it's called.) Same basic thing.

 

[Quvack]

I have a feeling making an adaptor the way you'd want is more trouble than what is it worth, its easier to grab a normal GB(C) cart and mod it to use an eeprom instead of the normal rom, theres are also plenty of tutorials on how to build cheap/suitable eeprom programmers, i've modded a number of GBC carts without any real issues and im not very knowledgable when it comes to the electronics side of things. You can easily get a suitable EEPROM from an old motherboard or something like that, video card, network card, etc.. i had shitloads of them lying around the house when i looked

Sorry that this doesnt help much with what you were trying but I feel that'd be a difficult project to say the least with all the things you have to deal with. If you want any help with the other ideas PM me or something and I can help with links and some tips and stuff. Good luck whatever you try though!

Also with just a memory card you wouldnt have the MBC chip or whatever they are called from the GBC cart (kinda like a NES mapper), which you need to be able to use it. However, if you modded a MBC5 compatible cart with a large enough EEPROM you'd be compatible with most 'software' for the GBC and fairly covered for any 'homebrew' work you may be interested in

 

[HyperHacker]

You might be right about EEPROMs on motherboards and such, I'll look around. How would I identify them? If I could get my hands on one I'd be more than happy to mod a GB cart instead of going to all the trouble of using a memory card. Also for the memory controller issue, I intended to have it built into the adaptor itself.