NES plug-in prototype created and working (last update: 2016-12-11)

[slot9]

I'm so excited by this news!

[Ness and Sonic]

This would be nice to see on Stone Age Gamer.

[Wannado]

Status update
Since I updated the OP in January, I had absolutely no time for the NES plugin or any other Retrode feature.

I'm still determined to improve the NES plugin design to make it easier for others to build one, or maybe even more.
But don't expect anything soon. I'll probably only have a few hours to spare for this every week.

Edit: See the OP for the most recent status.

[Nori]

So at the moment SRM transfer is not yet possible?

[Wannado]

So at the moment SRM transfer is not yet possible?

Reading SRAM from NES cartridges is working for the games I tested, writing SRAM is still on the to-do list (see original post).

[EvilDragon]

Status update
Since I updated the OP in January, I had absolutely no time for the NES plugin or any other Retrode feature.

I'm still determined to improve the NES plugin design to make it easier for others to build one, or maybe even more.
But don't expect anything soon. I'll probably only have a few hours to spare for this every week.

Great I'm still up for mass producing it, when it's finished

[Wannado]

Status update
Since I updated the OP in January, ...

Great I'm still up for mass producing it, when it's finished

I have updated the OP again in the meantime, though not much has changed (except that I now at least did other Retrode stuff).

The prototype has two PCBs, of which one plugs into that NES spare part. For a mass-producible design, the plug-in should instead have only one PCB with the cartridge slot soldered onto it.

And that slot will probably be the biggest problem: 72 (2x36) pins with a stride of 2.50 mm seem to be rare. For a small series, Matthias suggested to saw apart shorter 2.50 mm slots, because we don't need the center pins. But that's nothing for real mass production. (Note: I have no idea how many or few people would be interested in buying this. Nevertheless, I'll try and make it as mass-producible as possible.)

Using 2.54 mm stride slots seems inacceptable to me, the risk of short circuits is too high: 0.04 mm * 18 = 0.72 mm = 28,8% of a pin, and if you don't center the cartridge perfectly, the offset will be even greater.

Edit: The 72 pins are 2x36, so the half width of the slot is 18 pins, not 36.

[EvilDragon]

Thanks for the info!
I'll check with my production facility whether they can source these!

[Ice Man]

Just saw this plugin and indeed would love to see more.

Here's a small suggestion.

Why are you using the original NES mechanic connector instead of a solder NES connector like the kazzo or Retron consoles? It's much easier to deal with, doesn't bend pin easily and is is cheap to get as well.

That way you can do everything on once PCB and someone could print a neat 3D case for that, too.

[Wannado]

Why are you using the original NES mechanic connector instead of a solder NES connector like the kazzo or Retron consoles? It's much easier to deal with, doesn't bend pin easily and is is cheap to get as well.

See reply #21 above. The solder connectors I managed to find so far had the wrong stride.

[Ice Man]

Have you tried the one from Tototek?
http://www.tototek.com/store/index.php?main_page=product_info&cPath=22&products_id=179

[Wannado]

The page does not seem to list any specifications for the connector. I noticed that they also offer EverDrives, but I have no idea whether that's legitimate.
@EvilDragon, do you know anything about Tototek?

Before I built my prototype, I spent many hours trying to find a suitable connector, and I only found the NES spare part. I hope that EvilDragon will be more successful.

For a new prototype, if I get around to making one, I will use sawn-off pieces of shorter connectors.

Note that I am also aware of the threads on the Nesdev forums where people discussed the use of connectors with the wrong stride. I guess, if you can ensure that the cartridge is centered properly, and if the connector has narrow contacts, it may work. But I'm not a fan of such a solution.

[Ice Man]

I've bought this NES connector for my kazzo NES/FC dumper and it works great with all NES carts. Never had any issues yet. It's a solder type connector.

[Wannado]

Could you please try and measure the width of one row of 36 pins on that connector?

With 2.50 mm per pin, one row would be 9.0 cm (about 3.54 inches) wide. However, that includes 36 gaps, and there are only 35 gaps between 36 pins. With 2.54 mm (0.1 inch) per pin, the row would be 9.144 cm (3.6 inches) wide.

[Ice Man]

Will do, when I get my Kazzo back. I've borrowed it a friend.