> As to what _else_ it is doing, and why it has the cable to the main
> card... I think that it must intercept MSYN from the processor and only
> let it pass if there's no hit in the cache.
> (To explain why it would need to do that... normally with the MS11,
> there's a static partitioning between FastBus memory and UNIBUS A
> memory. So when the CPU goes to do a memory cycle, it can put the
> address out on both the UNIBUS and FastBus, with the certainty that it
> will only get a reply on one.
So, my guess was wrong there. I had _assumed_ that when doing a memory
operation, the CPU started a cycle on both busses, to minimize the delay on
the UNIBUS cycle if the MS11 on the FastBus didn't have that location. (I had
previously checked, and there is an 'I have that location' signal which the
MS11 sends back, making the concept of a cache possible.)
Well, no. In the "KB11-A CPU Maintenance Manual" (DEC-11-HKBB-D), section
7.7.1 ("Bus Control Introduction"), it says:
If the address applies to a Fastbus device, that device will respond in time
to inhibit the UNIBUS MSYN signal
(It turns out the KB11-A is very clever; it has to delay for a bit after
asserting the address, etc, signals on the UNIBUS, for de-skew, before it can
assert MSYN, and during that delay, in parallel, it checks to see if the MS11
has that location.)
So my theory about what that double-card does (prevent an MSYN sent to main
memory on a cache hit) is apparently wrong.
Which leaves the question of what that card _does_ do...
The cache _does_ need to have the A and B UNIBUS tied together, so that it can
snoop UNIBUS memory cycles (which are on the A UNIBUS) via the B UNIBUS (which
is what it has access to on the backplane), _but_ it doesn't need a special
card, with i) active logic, and b) a cable back to the main board, to do that
- a regular M9200 will do that.
The cable back to the main card, and the logic on the two dual-width cards,
mean it wants to interfere somehow in the connection between the A and B
UNIBUS. But if not the MSYN thing, what else could it be? I have pondered
that question, but I can't think of anything.
It can't be doing anything with interrupts or DMA, I would think, so no grant
interception. So what else could it be? Anyone have any ideas?
Noel
I have a bunch of Able items here If you have any questions, please
contact me off list.
If you have any info, please share it with us.
several models of Quniverters
10028, 10028101, 10028102 some boards have 3 #s This is the mysterious PDP
11/45 board. RARE?
10033, 10033001, 10033002 PDP1134, 11/40 cache RARE? SN267
10003000, 10003001, 10003002
10049, 10049-0, 10049001,10049002 High speed link
Datasouth board for LA36 I believe.
This is a very old rack mount disk controller (has format switch) with what
looks like ims on the 15 or so small boards. The backplane has DYNATECH on
the back.
Two Unisys PCK105-SKB look unused, but one is yellowed.
DATAMYTE 1000 Data Collector
EECO model # TRS9200BBDED, paper tape reader, no reels. The TRS9200 is on
Bitsavers.org
I have some old Targa 1.0 video boards (dating back to their AT&T days) but
no driver diskettes. Does anyone happen to have some? I think they should
work with Targa 16 drivers.
> I am looking for a manual for the original NEC Multisync monitor.
Mine is JC-1402 and the "User's Manual" I have is titled "MultiSync 3D". It mentions model JC-1404 but it all looks the same as mine. Is there anything in particular you need to know - or would you like a scan?
Richard Sheppard
Hi,
I have an working VAX4000/300 and I'm looking for additional memory for
this machine. Has anyone left over MS-670 Memoryboards that he wants to
get rid of for an symbolic price? (or compatibles, clearpoint etc...)
I'm ocated in germany..
Regards,
Holm
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
info at tsht.de Fax +49 3731 74200 Tel +49 3731 74222 Mobil: 0172 8790 741
I am looking for a sort of 'hello world' example and/or samples to use the graphics library in this compiler, some sample code. My target is DOS and the Compaq luggable mono display.
It looks like its all there, the library and include files for display adapters and modes, but I cant find an example on the netwebs to get me started.
Anybody have a set of demo files or application source to study and to use this?
I have TurboC running on this machine, and the graphics are great. Did Microsoft have a similar set of examples for Fortran?
Randy
The following can be delivered to VCFMW or shipped:
IBM 5152 personal computer graphics printer
Panasonic MX-P1124 24 pin multi mode printer
Several Calcomp table top plotters
Versatec Unibus boards
DEC SC08 Star Couplers
Just looking for reasonable offers.
Thanks, Paul
*VCF PNW 2019 will take place March 23-24, 2019 at Living Computers:
Museum+Labs in Seattle, Washington. We had a great time last year and we
are going to try to make it even better this year.Exhibitor registration is
open. I am also looking for speakers and volunteers to help me run the
event. It seems early but time tends to speed up at the end of the year.
Getting an earlier start should also help people who need to make travel
arrangements.Are you thinking about traveling from outside of the region?
There is plenty to do in Seattle while you are here, including the
Connections Museum, the Pacific Science Center, MoPOP, the Boeing factory
tour, etc.Interested? Check out
http://vcfed.org/wp/festivals/vintage-computer-festival-pacific-northwest/
<http://vcfed.org/wp/festivals/vintage-computer-festival-pacific-northwest/>
for more details or send me an email.Thanks,Mike*