Replying to various things without re-quoting:

Here's a stackable dual-row header: http://www.digikey.com/product-detail/e ... ND/1111810
Although the price is kind of high, note that in spite of the picture, the part is actually a strip of 100 pins, and you can cut the lengths you need from it, which is what I do. There doesn't need to be any waste, because shorter leftovers can be put end to end to make longer connectors. I think the dual-row headers are more common, because of mating IDCs that clamp onto ribbon cables with wires at .050" centers.

Here's a Vector RE96MWR right-angle (for the cards in a cage) 96-pin (3x32) DIN 3-row wire-wrap male connector, Mouser stock number 574-RE96MWR:
http://www.mouser.com/ProductDetail/Vec ... VFVA%3d%3d
These are most commonly used for VME bus, and industrial card-cage computer bus. I bought a few of these connectors for cards for the workbench computer I'm building in a half-rack-width 3U Eurocard cage shown at viewtopic.php?p=45607#p45607 . I took the pictures before I had made much progress on it. There's no picture of the connector on the Mouser page, but click on the .pdf link there to get the datasheet which has excellent drawings of it. The mating female that I use in the backplane is the Vector RE96FW which I got a tube of for pennies on the dollar at an electronics swap meet. Its Mouser stock number is 574-RE96FW, and the link is:
http://www.mouser.com/ProductDetail/Vec ... GBlsgks%3d
It is shown as "Style 2" in the top row of pictures in the same .pdf datasheet.

Here are various card cages. I realize you're interested in something much smaller; but there no reason you can't implement the idea with much smaller dimensions. Imagine a card cage so small that the cards are SD-card size!





PC/104 aluminum-railed card cage (90x96m cards, no backplane):


This is the automated test equipment I built at my last place of work, about 1991 and using STC bus, shown in my project pages on this site, first with the top and front panel off, showing the cards in position and plugged into the backplane, and then all buttoned up and being used to test a board:

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Those pictures really speak to me! I'm serious (voices in my head...lol).

Seriously, I'd love to make a back-plane design like those. I'm the kind of guy that gets all excited when I see the S-100 bus. I realize times have changed and back-planes aren't in fashion any more (not to mention not practical these days for high speed circuits).

But I still can't shake the desire to build a computer like those. The ProtoBricks were an idea for super-fast prototyping because I hate messing with breadboards. At least for large circuits. More like Lego pieces to build a solid, working computer.

I really don't know which is more practical for prototyping. Stackable bricks (shields) or back-planes. The Arduino world has proven that shields at least have a thriving ecosystem. Shields also seem cheaper to build than large back-planes.

I spoke with the man who did the RC2014 and I have to admit, I like what he's done more than the shields, however.

There is just something so "retro" with a back-plane.

_________________
Cat; the other white meat.

I have a short discussion of expansion buses and interfaces at http://wilsonminesco.com/6502primer/ExpBusIntrfc.html, part of which addresses exactly what you're saying. There's no reason you couldn't make a tiny one though! The small size would get rid of the long connections and make it more suitable for high speeds. VME bus is not small, and it's fast (VME320 will do 320 MB/s), but the engineering behind the bus transmission lines is well beyond most hobbyists. For a small backplane, you could use something like this Sullens board-edge connector with 44 pins on .100" centers which shows up quite a bit larger than actual size on my monitor and was used for the C64 expansion port,

or pin headers on the same .100" centers, with as many as three rows, giving 45 contacts in 1.5", 60 contacts in 2", etc.. The Samtec SSW catalog pages are attached (just two pages).

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Well, for me, high-speed would be in the 3-4MHz range. My target computer will be in the 1-2MHz range. Think Apple IIe meets Commodore 64. If you think about it, those were some large boards!




I love those connectors! I actually have a few in case I need them for my Commodore's. I thought about using the same edge connector used in the Apple IIe. That would be a great throw-back to that era.

_________________
Cat; the other white meat.

I've run into Samtec before when I was searching for stacked headers. They have excellent web pages that let you customize the SSW and/or SSQ connectors that you want. For stackable headers, just select lead style "-03". The pages will give you a 3D rendering of the type you're building, and can generate CAD drawings or datasheets for your connector too. I wish every manufacturer would do that!

Unfortunately, Mouser (who are my favorite because they carry both WDC and Parallax parts) isn't a distributor for Samtec, but Digikey has them (Click here and do a search for SSW or SSQ). Unfortunately they don't have 2-row 50-pin (25 "positions") connectors that I would need for future expansion boards for my project but they do have single-row 25 pins stackable headers.

===Jac

EDIT: the difference between SSQ and SSW is that SSQ connectors have square pins (0.025x0.025 inch) whereas SSW connectors have "solder tails" which are not square. So for stacking headers you will probably want SSQ.

I've bought directly from Samtec. Samtec probably allows that on the basis that they know it's not possible for the distributors to stock every possible part. Many combinations of options are only made up when they're ordered. What I don't remember is if Samtec's minimum order is too high for some hobbyists (like $100).

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?