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pearce_jj
August 10th, 2011, 03:18 AM
Just wondering if the above ever actually existed (i.e. with two or more 8086 or 8088's), and if so what operating system would have been used?

krebizfan
August 10th, 2011, 07:04 AM
Just wondering if the above ever actually existed (i.e. with two or more 8086 or 8088's), and if so what operating system would have been used?

I think that Compupro supported multiple 8086 cards and there was customized variant of MP/M-86 or its successor DR-NET that could handle the multiple CPUs. Other OS options were possible but probably needed a bit of customization to match the specific set of cards in a given Compupro.

Chuck(G)
August 10th, 2011, 08:00 AM
"Multiprocessor" is a rather nebulous term. Do you mean SMP-type where both CPUs are running at the same time, sharing the same memory? Or the case where only one CPU at a time is running at any one time, or the case where each CPU has its own memory?

pearce_jj
August 10th, 2011, 08:37 AM
Interesting, thanks.

According to this there are several options for it:
http://www.parl.clemson.edu/~wjones/371/gowdy/documents/materials/8086MultiprocessorConfiguration.pdf

Including pairing with an IO offload coprocessor, the 8089, which I'd not heard of up until now.

Chuck(G)
August 10th, 2011, 09:59 AM
The 8089 was supposed to solve the rather kludged-up DMA issue of using an 8085 part (the 8237) for 16-bit DMA. It had a 20-bit address bus and register set, but the cost, coupled with the requirement for its own programming/ROM never made it very popular. The 80186 could already do 20-bit address DMA in either 8 or 16 bits, so there was no need for it in the embedded market. By the time the 80286 was released, the 8089 was a dead duck--it lacked the extra 4 bits of the 286 physical address bus--and traditional 8237-style DMA was becoming less popular because of the rise of bus-mastering DMA and falling memory prices (each peripheral could have its own memory).

Pretty much born an orphan. I remember the Intel sales guy wrinkling up his nose when I asked about it.

luckybob
August 10th, 2011, 10:29 AM
I bought What I believe to be a 4 port high-speed serial card off ebay a while back. The darn thing had a 4mhz 80286 AND a 6mhz 80186 on the same card and it appeared to have 4Mb of ram. Quite an insane card if you ask me. I ended up putting it in some box and it sits on my shelf. While its not "smp" or "multi-processor" in the conventional sense. Its still pretty awesome.

Chuck(G)
August 10th, 2011, 10:45 AM
Bob, care to post a photo? I may know what the thing is--really not a serial card at all.

There were a few systems that used the 80186/80286 setup--I/O going through the 186 with the 286 running Xenix.

pearce_jj
August 10th, 2011, 11:02 AM
+1 for some info on that particular beast!

luckybob
August 10th, 2011, 11:30 AM
Just took these with my camera:

64196420642164226423

Pic 1: The front view
pic 2: Closeup of the serial port controllers. 2x D8274 1x P8253-5
pic 3: closeup of processors left to right, C8207-2, C80186-6, C80286-4
pic 4: backside
pic 5: The memory. each simm? has 4x mostek MK4564E-20 (64k x 1)

not pictured is the dongle cables. They connect at the card via 2x9 header connectors and split into 2x female db-25 connectors.

I made a post here about this board when I got it back at christmas:
http://www.vintage-computer.com/vcforum/showthread.php?23192-mystery-dual-cpu-single-board-computer&

pearce_jj
August 10th, 2011, 01:16 PM
Did you ever get the code out of the EPROMs?

luckybob
August 10th, 2011, 01:17 PM
no, I dont have any sort of reader. :( Havent had the money to get one either.

Chuck(G)
August 10th, 2011, 02:28 PM
It's a PC Technologies "Xtender" board. See Infoworld article here (http://books.google.com/books?id=xS4EAAAAMBAJ&pg=PA45&dq=Infoworld+80186+80286+serial&hl=en&ei=7ARDTrjzFOjTiALSxKSpBQ&sa=X&oi=book_result&ct=result&resnum=7&ved=0CEEQ6AEwBg#v=onepage&q&f=false).

I thought I recognized it.

luckybob
August 10th, 2011, 02:35 PM
It's a PC Technologies "Xtender" board. See Infoworld article here (http://books.google.com/books?id=xS4EAAAAMBAJ&pg=PA45&dq=Infoworld+80186+80286+serial&hl=en&ei=7ARDTrjzFOjTiALSxKSpBQ&sa=X&oi=book_result&ct=result&resnum=7&ved=0CEEQ6AEwBg#v=onepage&q&f=false).

I thought I recognized it.

you are now and forever my favorite person!

NobodyIsHere
August 12th, 2011, 02:40 AM
Hi! John and I are working on an S-100 8086 CPU board which supports the IEEE-696 multiple bus master logic. I think at least in theory two or more of these boards could be installed on an S-100 bus to form a multi-computer. Each CPU would run its own instance of MS-DOS, FreeDOS, or CP/M-86 though. John is already running the prototype board in tandem with the S-100 Z80 CPU board so this seems at least plausible. I am not sure if this is what you are asking about though.

Thanks!

Andrew Lynch

pearce_jj
August 12th, 2011, 04:17 AM
Thanks very much indeed for all the replies on this one! Andrew, I'm very interested in that, do you have any more info anywhere?

pearce_jj
August 12th, 2011, 08:19 AM
To add, I just read through that article - superb! - how did you find it!?

Chuck(G)
August 12th, 2011, 08:31 AM
I went back in my paper files and found my notes on "competition"--I was consulting for another company making an 80186/80286 box--and found the company name "PC Technologies". Armed with that, it was a matter of a simple Google.

FWIW, the 1987 sales numbers for the thing were only in the double-digits. So not really popular.

pearce_jj
August 12th, 2011, 08:35 AM
A truely amazing memory.

So have I got it right that this card, with it's MB's of RAM and two full processors, enabled an XT to be accessed from four terminals concurrently for presumably text-mode DOS apps?

Chuck(G)
August 12th, 2011, 09:33 AM
Their original plan was to market the thing with 286 Xenix, but I don't know if that ever happened. AFAIK, they only offered DRI Concurrent DOS. But yeah, 4 terminals + the XT native = 5 users.

OTOH, we did offer Xenix for the Poppy II and, in fact, based all our applications on it.

luckybob
August 12th, 2011, 10:32 AM
Sales in the double digits you say? So that means it was well worth the $5 I paid for it? ^.^

Not to thread hijack, but if anyone wants this thing, I have no use for it. It is just going to collect dust in its box on my shelf.

NobodyIsHere
August 13th, 2011, 09:17 AM
Thanks very much indeed for all the replies on this one! Andrew, I'm very interested in that, do you have any more info anywhere?

Hi! Yes, this is another S-100 board we are working on at the moment. This one has been difficult and required three prototypes to get it working properly.

http://n8vem-sbc.pbworks.com/w/browse/#view=ViewFolder&param=S-100%208086%20CPU%20board

The final board is just finishing up its PCB trace routing information and should be available for the S100computers.com and N8VEM-S100 builders in the near future.

For sure there will be an announcement on N8VEM-S100 mailing list so you might want to register there.

http://groups.google.com/group/n8vem-s100

Thanks and have a nice day!

Andrew Lynch