Has anybody made a DIY memory card?

[Deferf]

There is very little information about custom Memory Cards. It is known that MCs are only modified SD cards. Is it possible to make one with huge capacity out of a commercial SD?

[Deferf]

I'm not talking about SD-Gecko adapters, but something to store your savegames.

[tueidj]

They're not modified SD cards. Maximum capacity is only 16MB.

[Deferf]

Anyway can they be made out of components? Or something like spoofing them

[pyroholic]

I think it should be possible to build one using a micro controller that can act as an spi-slave connected to the memory card slot and also connect the micro controller to a storage unit, sd-card, spi-flash or similar. Looking at the picture of a memory card in this thread viewtopic.php?f=26&t=666 it looks like an arm-controller connected to some flash-circuit.

[Sierron]

I've been looking around online because I were interested too about making one on my own.

As Macronix never released the datasheet for the MX25L4001 it's impossible to actually check what the internal is. Looking at a original 59 blocks memorycard there are many pins (14 on one side and 4 other side connected to ground - might not be even needed and N.C. most likely). The package of the chip is probably - if I'm not mistaken - just a different package to stop others making them their own (Macronix has no SOP28 chips ... many of them are SOP8). In the end it's just speculation.

As for the chip Datel used, the MX25L4004 (according to yagcd), I've found a datasheet. Can't really find any kind of supplier but apparently chinese sites sell them. I've looked up a programmer for that thing go around $150+.

Beside all those things: the chips have 5 blocks (40KB) occupied with some data which might be the code programmed on the chips and filesystem related stuff.

We need the chips, the programmer and the code used to program those chips the same way nintendo/datel did...

Oh and before I forget it: the W29C040P-90 chips mentioned on yagcd as 3rd party ... here is the datasheet (90B variant). Programmer for this go for $130.

I think it should be possible to build one using a micro controller that can act as an spi-slave connected to the memory card slot and also connect the micro controller to a storage unit, sd-card, spi-flash or similar.

Might be easier than doing all the other stuff above. We just need a way to disguise them as valid memorycards.

Looking at the picture of a memory card in this thread viewtopic.php?f=26&t=666 it looks like an arm-controller connected to some flash-circuit.

Tried finding some info on that arm controller but nothing popped up on google or sites related to such chips. The Samsung chip K9F2808U0C-YCB0 is a probably a NAND Flash Memory - the K9F2808U0A-YCBO version might be a earlier version. So the ARM chip could be a NAND Flash memory controller. There are many results for that search term on google but finding the right version ... good luck. If it's something generic we need someone who can read out the code on the chip so we could clone them.

yeah ...

[tueidj]

You don't need to clone anything or re-use the exact parts from other memory cards. The protocol is well known so it would be relatively easy to design something from scratch.