nesdev.org

Hello everyone. I'm new to the homebrew publishing scene, but have been working on a game for over three years.

I'm looking to put my game and production using one of the MMC1 boards sold by RetroZone. My game only needs bank switchable CHR-ROM, and 16 banks of PRG ROM.

I'm trying to decide whether or not to add 8K of WRAM. Currently I have things working without it, but I could add some nice enhancements with just a few more pages of RAM.

How expensively could one produce such a cart?
Is it possible to buy in bulk to save from RetroZone?
And are there other options?

Thanks in advance, Carl

Cost is heavily dependent on how many you're buying. There is also the issue of getting your hands on a MMC1 (and CIC potentially). Then there is always the case. But since you didn't ask I'll ignore the CIC and case.

You would have to get the MMC1 onto a cpld. The one that retrozone uses is a xilinx xc9572

http://search.digikey.com/us/en/product ... -ND/966625

They are $5-7 depending on how many you buy. You might be able to find a better price or smaller/cheaper CPLD that will work, but that one obviously works.

If you design the PCB yourself and order 100 or more you should be able to get the PCBs for ~$2 if you ordered from the right place. Just guessing though... They will run $15 or more if you only buy a few. and dirt cheap if you buy in the 1000s.

EDIT: don't forget to add the cost of getting a couple boards prototyped. Easily $50.

Plus you have to implement the MMC1 onto the CPLD. It helps that Bregalad has created and simulated them and posted the schematics here: http://nesdev.com/bbs/viewtopic.php?t=8277&highlight= This is also something I plan to do in the next couple months, porting his design over to Verilog and testing on a CPLD and the NES that is.

But even if you did all that you're still only going to save a couple dollars each if you were to make 100 of em. So while some don't like to support the way he does business, it's hard to beat the price unless you're producing in the 1000s I would say. You would have to contact him to find out if you can get any discounts. If your lucky I would guess you could get a small discount, but I wouldn't expect anything. If you're buying cases and CIClones from him as well you might be able to get a better deal.

Why not using one of SKROM boards?

Or making a cloneby using these parts :
27Cxxxx --> PRG and CHR
6264 --> WRAM
KS5361 --> MMC1 clone

Maybe you could use the board I made. It's not MMC1, but it effectively supersedes it.
http://nesdev.com/bbs/viewtopic.php?t=8 ... sc&start=0

I'm hoping to have it working properly by the end of January. It should have been fully debugged by now but some unrelated stuff has been slowing my progress.

FARID wrote: KS5361 --> MMC1 clone

But I heard on another posts that these chips differ even from each other. Plus, where can you order 250+ of them for cheap?

And plus I like SUROM more, but I wouldn't die having only CHR-ROM still.

3gengames wrote:

FARID wrote: KS5361 --> MMC1 clone

But I heard on another posts that these chips differ even from each other. Plus, where can you order 250+ of them for cheap?

Not only that but from what I've seen of the MMC3 clones, only about 10% or less of the cloned chips actually work assuming you find a source of them. Not sure if the MMC1 clones have the same issue or not. Maybe it was just an issue of difference though, it's hard to know...

Memblers' 8T rom board is your best pre-designed option. And since you wouldn't be the only one buying boards the cost could be low especially if other people start releasing games on it. About the only thing that sounds like you'd have to change is your CHR-ROM, the 8T is CHR-RAM. But there's 32KB of CHR-RAM with 2KB bank switching so you shouldn't have to do much after filling it. Everything else about it is an upgrade from the MMC1.

make your own mapper on 74xx series