Questions about Gamecube memcard and SD card compatabilities

[Videogamer555]

I found some (far from complete) info on another thread about this topic. I found it while googling about this topic.

Original thread I had questions about: viewtopic.php?f=36&t=7994

As detailed as that thread is, it didn't answer everything I would like to know about this topic. So I joined these forums to ask these questions. However as that thread is several years old I decided to make a separate thread, rather than post in the old one.

None of these have been asked or answered on the above thread I linked to, so that's why I'm asking here. Now my questions are these:
What is the INT pin used for on a GC memory card?
On the SD card, why is pin 8 not being used for the GC to SD conversion?
On the SD card, why is pin 9 only being connected to the INT pin "only needed if making an adapter"?
Isn't the whole purpose of matching the SD to GC pinouts for making an adapter?
Therefore isn't the INT pin always supposed to be connected?
I've heard that only the Animal Crossing game in Japan uses SD card saves (but no other game does, nor will work with an SD adapter).
Why is this?
If GC card is the same as an SD card with just a few more pins (and most of those are extra power connectors I see), why couldn't an SD card be used to save all GC games?
They are both flash memory cards, just rearanged pins compared to each other, so why wouldn't a pin-to-pin adapter with an SD card work for all GC games?

 

[Blargaman91]

Re: Questions about Gamecube memcard and SD card compatabili

It sounds like you want to hear more technical answers, but I don't know much about the detailed workings of the memory cards or SD cards.
But for your first question, the INT line is simply a required data line on a GameCube memory card that helps compatibility. The memory card will act glitchy without it connected, though as for what it does exactly, I'm not sure. An SD card does have more data lines than a GameCube memory card, which is why pin 8 is left unused. There wouldn't be any place to connect it. Unfortunately, SD cards are know to act glitchy with the INT line connected, whereas real memory cards need it. That's why you should only wire it up to an SD card reader if you plan to make an "SD to GC memcard" adapter, since you're gonna need the INT for the memory card to work correctly. That would be why some people may not want to have the INT line connected, but for the sake of memory card compatibility, some might. So, that's what the "adapter" is; converting everything back into a memory card slot through use of the SD slot.
I believe the SD card adapter that Nintendo sold only in Japan for animal crossing had some kind of electronics inside - normally, it's just wire. Whatever Nintendo did made the SD card work, but wired directly, an SD card can't work like a normal memory for the most part because of file format, I believe (I'm not completely sure on this). I would think the GameCube memory card uses a file format that may be the same as WBFS, or it may be something else that's foreign to Windows or Mac OS. Likewise, FAT32 and the like is going to be foreign to the GameCube unless you use some homebrew software to make it work.
I don't know anything more, and I'm sure there is more to compatibility than file format, but I hope I could help anyway.