MD 16 Mbit SRAM cart

[andoba]

Hello, I'm making a schematic for a Mega Drive / Genesis 16 Mbit EPROM cart with SRAM support.

The cartridge is based on the Sonic 3 cart. It uses:

- Two 74LS00. Those are four NAND gates inside a single package. They are used for handling the write enable signals of the MD bus (UDSW and LDSW).

- 74LS74. A dual Flip-Flop IC. Used for SRAM access stuff I think.

- 74LS139. A dual 2-to-4 line decoder. Used for address decoding I suppose.

Here is the schematic from the point I am right now:



The schematic is made with ExpressPCB. Thanks to Devster for the Mega Drive connector component.

I hope it works. When I finish with the schematic, I'll buy the components and test it.

Cheers.

[andoba]

Done. Have fun.

[werejag]

ok can we get gerbers and how do you program it?