DIY NES cart

[KanedaFr]

Hello,

I'm a big fan of Akira and Venus War. Each one have its own NES game and, thanks to some great people, they were translated !
I read you need to find a cart with the same mapper (i need a MMC1 and a MMC3) but I also read you need to cut some trace and add some wires....and it's on this part I can't find good information....

So....somebody know how to (or link to learn to) make a NES cart ?

thanks

[HardWareMan]

I found the internet a couple of NES FLASH cartridges. They used the FPGA / CPLD as mapper. One of them used microcontroller and USB and can be flashed via USB. They can emulate some of popular mappers. FLASH cartridges with original mappers more prevalent and can be easy assembled.

[tomaitheous]

You could build the MMC1 chip with discrete logic (it's going to be a few extra chips too since it's serial data written to the mapper port). MMC3 would be more complex because it has an interrupt system that's driven from the PPU's address lines and has more address lines to multiplex/decode. Finding a cart would be simpler

Is this for PAL or NTSC? Lots of NTSC games used the MMC1 mapper.

Here's a list of games - here and a mapper doc - here

Also take care at looking at the rom hack and the iNES header. Usually translation hackers change the mapper and/or add features (like extra SRAM work ram).

[KanedaFr]

thanks, but I'm not looking for a flash or dev cart but a way to make a new cart. like http://nesreproductions.com/ for ex (no, it's not to sell it!)

Finding a cart would be simpler

It's what I want to do...a MMC1 and a MMC3 carts

Is this for PAL or NTSC? Lots of NTSC games used the MMC1 mapper.

Here's a list of games - here and a mapper doc - here

I used your first link to find the mapper needed by akira and by venus war

Also take care at looking at the rom hack and the iNES header. Usually translation hackers change the mapper and/or add features (like extra SRAM work ram).

oh ?! it could be a problem..I thought I just have to write the rom nothing else. How can I find if they changed something ?

[tomaitheous]

oh ?! it could be a problem..I thought I just have to write the rom nothing else. How can I find if they changed something ?

If the hacker correctly updated the header, then you can use this guide here. Some MMC1/3 games have and extra 8k of SRAM which is used for more work ram (the original system only has 2k). Games that have battery back also used the same amount of SRAM (8k) and it's in the same location. Another thing you need to look for is if the donor cart is using VROM or VRAM, and that you're rom image is of the same setup.

You can also ask over at the nesdev forums.

[KanedaFr]

thanks for the info...so I 'just' need to check if the header of the original rom is different from the translated one.

I'll check nesdev forum because I don't see how to check your last point (VRxM)

thanks !