I’ve been wondering this for a long time now. It’s basically a motherboard on an ISA slot. It has a processor, memory, and everything with an ISA slot to plug into another motherboard. I’ve been working on computers for a long time and I’ve never seen anything else like it. How would you use it? Here’s a picture.
It’s been years (10?) since I last saw this sort of thing. One sort of this card simply plugs into an ISA bus which is a pure ISA bus from which it gets power and can talk to other cards.
I’d say that’s a single-board computer, similar to (but not quite the same as) this one:
http://www.voxtechnologies.com/sbc/images/VTC0422-1.jpg
So this would plug into a board that’s similar to a motherboard, but only has an ISA bus? Are these boards considerably smaller than actual AT/ATX motherboards? Do they go in smaller cases? I was just thinking a few weeks ago that it would be cool to have a small computer that consumes little electricity to use as a software router.
It’s an SBC. (Single-board computer). They are typically used in backplane enclosures. Usually you see them on PCI buses these days, though.
A backplane allows you to construct several computers on a single bus by combining SBCs and whatever other kind of interface cards you need. A single backplane may have one SBC and a dozen PCI cards (for example, some kinds of telephone switching equipment is constructed this way). Or it could be a cluster of several SBCs sharing the same bus. (Some massively parallel-processing computers are constructed this way.)
Here are some examples of ISA backplanes:
Three-slot
Six-slot
Ten-slot
20-slot.
You can find just about everything in between, too. You can also find active backplanes with several types of slots (Mixing ISA, PCI, etc.) Backplanes is big business.
Things like this are quite common in industrial computers. Your board is almost certainly made for the industrial market, since it has a PC-104 connector on the board. PC-104 is a compact version of ISA that uses the same signals electrically, but uses a stackable connector system instead of a backplane so that the parts can be made smaller and fit together much more compactly. The board looks like it also has a slot for a disk on chip (might just be a ROM socket), which is another feature common in industrial computer boards. Disk on chip is a flash memory chip that the system thinks is a hard drive. Us engineer geeks like disk on chips because they can survive environments where temperature and vibration would quickly kill a mechanical hard drive.
PCI motherboards and PICMG (which has a PCI connector behind an ISA connector) are also common. In fact, they are more common. ISA alone is fairly rare these days, though you can still buy new ones.
Here’s a link to one of many manufacturers of similar products:
http://www.jenlogix.co.nz/products/sbc_half-isa.htm
(Note - I’ve never used this particular vendor so I have no idea if their boards are any good or not, just posting them here as an example)
If you really want small and low power, look into PC-104 and compact-pci boards. With these you don’t even need a backplane, so it’s pretty easy to put together a system that’s about the size of a brick and consumes less than 5 watts.
Really? How old is the technology? I’m looking for something cheap that will support two NIC’s and FreeBSD. Mini ATX seems to be new and expensive. Something around classic Pentium speeds would be sufficient.
Regarding this board I already have, what all specs would I have to consider on a backplane? Does it matter if it’s active or passive? (I don’t really know what the difference is in this context.) Must it support PC104? (I really can’t see how it’s different than normal ISA.) How can I tell if that slot is for disk-on-a-chip and are all such chips compatible?
By the way, the socket is labelled “M-System SSD”.
snailboy: For oddball hardware, there might be a better choice than FreeBSD. This is a website about running various flavors of *BSD on different routers. PC104 is mentioned.
This is not directly related to the original OP as I think that’s been answered, but one unique (and ill-fated) application of a slot-based computer was the MacIvory Lisp Machine that piggy-backed on a 68040-based Macintosh back in the late 80’s.
This was an honest-to-gosh Symbolics Lisp Machine that you could install inside a Mac and you could switch back and forth between the two machines. A great idea except that the card cost $10,000 and it ran pretty slowly.
Now that I think of it, for quite a while they were also selling Macs with an attached PC motherboard as well, so that you could run both Mac-OS and DOS on the same machine. Again, a good idea but as I recall, it wasn’t cost effective – it made more sense to buy two separate machines.
M-systems is who our company uses for flash disks. If the socket is labled m-systems then it is for one of their devices.
Here’s their web site: http://www.m-sys.com/
Probably the best thing to do would be to find the manufacturer of your specific board and see what the specs are. The manufacturer should list what devices are compatible with that board.
I think I wasn’t clear before. You have an ISA board that also has a PC-104 connector on it. The big edge connector on the bottom of the board is a standard ISA connector. The connector just under the flash disk socket and the ROM (and above the ISA connector) is the PC-104 socket. You can plug a PC-104 board onto this socket.
For example, here’s a PC-104 ethernet card: http://www.technoland.com/tl_pc104_lan01.htm
Note the connector at the bottom, and how it would plug right into the connector on the bottom of your board. Then another PC-104 board could plug into the ethernet card. It’s a stackable type system.
A google search for “ISA passive backplane” should get you a few dozen links where you can buy one from. Warning, industrial stuff tends to be a bit pricy. You may need to look around to find something affordable.
Here’s a backplane and a tiny case you could use on EBAY, and the price isn’t bad:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=97184&item=3880180311&rd=1&ssPageName=WD1V
You’ll need an external power supply. An old AT type power supply would work. You’d have to cut the connector and wire it to the case.
PC-104 and compact PCI have both been around for many years, but because they are in specialized markets the stuff still tends to be a bit pricy.
A passive backplane is one that is just a bunch of connectors. There’s no chips on it. An active backplane has chips on it. You’ll often see active backplanes for PCI or PICMG because you can’t get more than three or four slots on a PCI bus without using a bridge chip. A six slot motherboard has two 3 slot PCI busses on it that just happen to be next to each other so that it looks like one big bus. ISA, because it’s old and slow, doesn’t need bridge chips.
I poked around that EBAY link that engineer_comp_geek provided and found a great picture of stacked PC-104 connecters here (scroll down to first picture). Cool.
Very interesting guys. I think I have enough information to make this thing whole when I get ready. Thanks.