I want to use the expansion slot. Is there any kind of standard cartridge slot or something that will plug into the expansion slot? Have any of you used it? What do you plug into it?
I'm not aware of anything that ever used it (other than that unreleased Minnesota state ottery modem), which sucks because I'd like to get a connector for one also.
I removed that obscure connector and replaced it with a sawed-off ISA connector
However, it's was not perfect fit i had to bend the pins. Here's a picture how it turned out.
http://wwwk.heltech.edu.hel.fi/koti/sep ... od_exp.jpg
As far as I know, there was never anything official released for the expansion port. (I"m welcome to be wrong about that though)
Personally, I feel that it represents a much larger purpose to hobbyists.
For example, there are several pins that go directly to cartridge, bypassing all of the internals of the console. Since the port itself also has pins to the internal audio mixer, you could build a simple plug/dongle that routes auxillary sound from a NES cart (some Famicom carts have extra sound hardware) to the NES' mixer. (Say if you were adapting the Japanese CV3 cart to play full sound on an american NES)
I'm sure there are plenty of other good ideas out there for that port.
Here we go. From the FAQ:
http://nesdev.com/NESTechFAQ.htm#expansionport
Code:
# What is the expansion port on the NES for?
Expansion??? Um, it was rarely used, though on the Famicom it was used for many things, such as the 3-D glasses, Keyboard, Tape Drive (I think), etc. The NES had (as far as I know) two accessories which used the expansion port: the Miracle Keyboard Piano Teaching System, and the Baton Teleplay System, a modem device for the NES which offered head-to-head play on the NES and Genesis. I don't believe the Teleplay was ever widely released.
I'm pretty sure the Miracle Piano used the controller port. I don't have the piano, but I do have the NES adapter for one.
One sure think is that to have acess to the connector, you HAVE TO break six little pins of plastics that covers it, and so doing that would technically "do irreversible damage to the console".
My SNES have a very similar unused connector, but this time it is user-accessible.
The connector is covered by a break-off piece of plastic, which in turn is covered by a plastic door that snaps shut. If you break off the plastic but keep the door snapped on when you don't have anything connected to the expansion port, nobody will know nor care that you have used the expansion port.
Yes, but you HAVE to break the plastic. I don't suppose that Nintendo has planned to make anything used it, because they wouldn't ask people to break the plastic case of their NES, even if it wouldn't damage anything.
So Nintendo are really dummy to make a connector and not make it officially user-accessible.
I like the idea to use it as a sound expansion of the NES. Would it be possible to input a device with a 1uF cpacitor and a 100kO resistor in order to get famicom sound trough expansion sound ? This would allow the user to only break the plastic of the connector instead of oppening the NES to do the modifiction. (I had to re-open it a second time to fix my solders didn't hold for long and that was anoying).
The plastic there is meant to be broken off if the port gets used. Nintendo put the port there with the plastic on it, so yes they did plan for people to break the plastic to use the port.
Actually the sound is my expansion port plan for now. I've already got a modified famicom to nes converter that passes the sound to the expansion port. I've got a copy of Akumajou Densetsu (Castlevania III Famicom) on it's way to me. I just want what I plug into the expansion port to look somewhat decent.
I think this is the best way to get the famicom sound on a toaster setup because:
a: no internal modifications
b: totally portable (just plug into any nes!)
I'm not sure if I will need the capacitor and resistor or not. I plan on trying it with just a connection first and seeing what it sounds like. I'll try both ways and let you know what it does.
Using a ribbon cable connected to the exp port, and routing it out from under the breakaway plastic, you wouldn't have break the plastic, but you would have a ribbon connector hanging out.
One alternative I imagine (for the CV3 example) is to wire the cartridge connector's pins internally to the corresponding exp port pins (with a detachable point on the cable for when you don't want it connected). Thoughts on this?
Now, my understanding is that this port is a Nintendo proprietary plug type. Does anyone know a good way to make or otherwise buy a opposite gender plug for it?
-Rob
Yes rbudrick, that's exactly what I'm doing and why I'm asking about this (sorry if I didn't make myself clear).
I'm modifying a famicom to NES adaptor so that the extra famicom sound is routed to one of the pins that goes through the nes to the expansion plug.
Now I'm building something to plug into the expansion plug, but I would prefer for it not to look like a frankenstein creation. I also want it to be simple enough that I could make it for friends and they could just plug it into the expansion slot and be ready to go (using the modified famicom to Nes adaptor also).
There's a round hole next to the expansion slot. I figure if I have a small board with some sort of peg sticking out that I can use that hole for a guide to make sure the plug is plugged in the right way.
ps if anyone has any games with the famicom to nes converters that they're willing to sell, I'm certainly interested. Lots of the original 1985 games were on famicom boards with a converter inside the board. Those converters are perfect for this project! I also have a casing worked out for the boards (which I will bring up here closer to project completion).
Bregalad wrote:
they wouldn't ask people to break the plastic case of their NES, even if it wouldn't damage anything.
Initially, Nintendo said not to insert anything at the Game Pak edge connector. Nintendo changed this when the Cleaning Kit came out.
But if you're going to run the Famicom cart sound through the adapter, then you can't just use the adapter from that robot game unless it has a trace for the expansion pins (which many games lack), and if your console doesn't respond to -5V (as is common for newer NES units), then you're going to have to open the NES anyway to cut pin 4 of the lockout chip.
I'm using the offical famicom to nes converter that Nintendo used in many of it's 1985 released games. Many of the earliest NES games were first released on famicom boards with US release roms with a famicom to nes converter in a NES cartridge. This was in the official earliest 5 screw US release of many games including excitebike, hogan's alley, gyromite, and many more. I'm post pictures of one of mine later.
It has a lockout chip already on the converter so I don't have to worry about that.
Yes, modifying the famicom to nes converter does require changing a trace so that the sound goes to the correct pin to reach the expansion port on the bottom of the nes. It's just basically soldering a wire, so it's no big deal.
I also have an interesting solution for a case for the modified famicom to nes converter which I don't want to let out of the bag yet! I can use my super powers for good or for awesome. This time it's going to be awesome!
Now that I have the sound routed internally to the expansion port, I just need to connect two pins on the exansion port. It's a very easy thing for me to do. I just want a way that it would be easy for anyone to do it. I want to be able to make a connector for my friend and for him to be able to just plug it in and go!
I've gotta say, I didn't think anyone would take my suggestion seriously.
Congrats on undertaking such a nifty project w/o hacking up your console. Just be sure to treat us with some instructions and sound samples when you get it all working!
Also, if it helps, I think one of the documents out on the main page referenced the kind of 25pin connector that mates with the expansion port on the NES. Offhand, I seem to recall that the author mentioned that compatible plugs are hard to find but there are generic parts out there that'll do the job.
Who knows, maybe this'll open the door for easy to deploy dev systems too (special cart + expansion device + normal console = dev station)?