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Hardware > Whats inside the DS Mem Exp cart ???

#169325 - dtp30 - Fri Jul 03, 2009 8:21 am

Hello all,

Does anyone know what is inside the DS Memory Exp Cart?

Is it just 8 MB of SRAM hanging off were the rom chip should be? Or does the custom nintendo chip thats on the board contain any flash with somthing on it?

Thanks guys,

Tim.

#169326 - cyril_sy - Fri Jul 03, 2009 10:25 am

Hi !
Yes it's a SRAM chip, but addresses and data are multiplexed on the ROM bus.
If you understand VHDL you may check this. It shows how to interface a RAM with the ROM bus.

#169327 - dtp30 - Fri Jul 03, 2009 11:18 am

I`m not up with VHDL. But if the lines are multiplexed. I presume i need a de-MUX to connect them to the SRAM chip. Would this chip be off the shelf? Or a custom in a standard GBA cart?

Thanks,

Tim

#169329 - cyril_sy - Fri Jul 03, 2009 12:37 pm

I'm not up with real hardware :p
You can find useful informations on custom gba cartridges on this website.