nesdev.org

Hi,

I am working on a multi platform gaming system. For the NES part i buy (some years ago) A31721-ND slot.I read on this forum that i can't work because of a pitch problem but it seems that some people use it (here).

Some one as the right answer ?

Thks

The "best" answer we've found is two card-edge connectors (one 30-34 pin, one 34 pin), with a slot cut out of the end, facing each other, spaced such that the "metric inch" (of the actual connector) vs "real inch" (of purchasable card-edge sockets) difference is consumed in the unused EXP pins.

Do you have a P/N of this kind of slot ?

You says that some pins are unused, it's really unuse or just useless ?

http://wiki.nesdev.com/w/index.php/Cartridge_connector

The EXPx pins only go to the expansion port on the bottom of the NES. A very small number of PCBs connect anything to them at all, such as the MMC5 boards.

The US toploading NES doesn't include metal contacts for most of the EXP pins.

Ok thks. So i need to buy new parts and rewrite my pcb schematic

lidnariq wrote:A very small number of PCBs connect anything to them at all, such as the MMC5 boards.

What do the MMC5 boards connect to the expansion pins?

oh.. so if i don't map this pin, some game will not work ? if yes i need all pin so the 2 slot method will not work ?

No, no games require anything from the expansion ports. If anything is ever connected to them, it was unused and not required by the game.

rainwarrior wrote:What do the MMC5 boards connect to the expansion pins?

EXP5: for MMC5 carts with PRG RAM, connected to PRG RAM /OE, pulled down on-cart with a resistor. I have absolutely no idea why they thought this was useful or interesting.
EXP6: ultimately connected to MMC5 audio, if all audio mixing parts (R1, R2, R4, R9, C2, C3) are populated.

[quote="lidnariq"
EXP6: ultimately connected to MMC5 audio, if all audio mixing parts (R1, R2, R4, R9, C2, C3) are populated.[/quote]

It happen on some cartridge ?

No, no US/EU MMC5 cartridges were ever shipped with the audio mixing hardware populated. Correspondingly, no US/EU MMC5 games use the audio generation hardware.

Some people may have populated the parts and put on EEPROMs to play music and/or homebrew or romhacks, but that's it.

ok cool, it's fine for me. But i have to found small slot. Do you have a website and a P/N that you already test ?

I've installed an A31721-ND part on my NES (bent the leads and sorta made it into a top-loader), and have been using that without any notable problems. With PCBs of my own design, and Game Genies, I've found that I can make it short if I purposely slide it to one side (I haven't tried this a whole lot with Nintendo's carts, I think they shorted also but it was fewer pins shorted, though PCBs will vary). Sliding the other way is fine. 99% of the time, when I put a cart in like normal, it just works. Surprisingly.

If you really need a perfect pitch connector, you can get one from a Game Genie. From what I've heard (haven't seen it in person myself), NES clones, and that "Blinking Light Win" connector all use that same A31721-ND (or similar) part. The concerns are understandable, but maybe a bit overblown.

Memblers wrote: If you really need a perfect pitch connector, you can get one from a Game Genie.

And simultaneously integrate the Game Genie functionality into the console. That would be cool.

thenendo wrote: And simultaneously integrate the Game Genie functionality into the console. That would be cool.

It would be, but the Game Genie does have some bugs. It causes the intro to be skipped on a lot of games because it doesn't wait for start to be released, and it messes up the sound in maybe most Capcom games. I actually made a build of ROM that fixes those bugs, if anyone wants it. I haven't released it because I haven't yet tested blargg's bootloader that I put into it, not sure if I can duplicate his setup, so it's been put off until I write some PC-side software for it.