What's the recommended method for adjusting the track 0 switch and track 0
stop on a Tandon TM100-2, if you don't have an alignment disk? I do have a
scope.
Mike Loewen mloewen at cpumagic.scol.pa.us
Old Technology http://q7.neurotica.com/Oldtech/
I can archive your disk content if you end up needing some assistance.
I have a few Vector Graphic machines with 100tpi Micropolis and Tandon 100-4M drives as well as Mod-I drives at 48tpi. I also have utilities to archive and recreate disks on these drives by exchanging the disk image with a PC via XMODEM (FLOP2PC and PC2FLOP). Note that these disk images can also be mounted and run under SIMH.
Mike
I just printed some board handles for a 32k OMNIBUS board (thanks Vince
Slyngstad, et al.) I now notice that all the OMNIBUS boards have an extra
0.1in spacer between the board and the handle. UNIBUS and QBus boards and
logic flip chips don't have the spacer.
Anyone else notice this and understand why?
The only thing I can see is that it might adjust for the over the top
connectors used on a lot of OMNIBUS boards.
-chuck
Re:
"My next project once I finish my IBM 1410 FPGA implementation (so, a
couple of years out, probably) would be to write an emulator for the
boat anchor known as the IBM 8100. I had exposure to these things back
in the 1980s."
I encountered one, once. Probably 1979, in a small conference room in
building 47U of Hewlett-Packard's Cupertino site. Sitting all alone in the
room. I was looking at it, and an HP engineer came in and explained
that they were waiting for IBM service to fix the memory board ...
the board HP had removed to look at closely :)
Now that I am finally getting my vintage computer accumulation
in order, I need a punched card file cabinet. Does anyone know
of one that might be available for purchase or trade? I am willing
to pick up anywhere in the western US.
In an ideal world, I would love to find one of the ones with a slanted
front on each drawer that holds a single card for a label.
I have an old wooden library catalog file cabinet (60 drawers) that
I would be willing to trade, as well as some DEC Q-bus chassis.
Any leads would be appreciated.
Alan Frisbie
When I worked at Apparat around 1981, we used a lot of *male* IDC edge card
connectors. I've almost never seen any since, and I couldn't remember the
name of the vendor. I just found out that it was Kel-Am, but the internet
knows almost nothing about them.
Here's an example:
https://www.elliottelectronicsupply.com/connectors/card-edge/male-card-edge…
That photo doesn't show the Kel-Am logo, which is just a stylized "KEL-AM".
There are some eBay auctions of the corresponding female connector (which
other vendors did make), some of which show the logo.
I wonder what happened to Kel-Am. Maybe they were acquired, maybe they went
under. It would be nice to find a copy of their catalog.
Speaking of which, it would also be nice to see some Robinson Nugent
connector catalogs from the late 1970s and early 1980s. I am especially
interested in seeing specs for their bottom-entry square-pin receptacles,
which I think _might_ be the ones used on Apple /// memory boards.
A friend and I are trying to get a PDP-11/70 running, and we'd like to get
a DHU11 async mux board. Anyone have an extra?
There's an Ebay listing claimed to be a DHU11, but that one is actually a
Qbus M3104.
Al Kossow <aek at bitsavers.org> wrote:
> On 8/25/21 4:51 PM, Alan Frisbie via cctalk wrote:
> > I recently acquired a Wilson Laboratories SX-530 disk exerciser
> > for SMD interface disk drives.? Unfortunately, it did not come
> > with a manual.? Does anyone out there have a copy they could
> > make available?? Yes, Bitsavers was the first place I checked.?
> it's up now under test equipment
Thank you very much! I've already downloaded it. I really appreciate
all the work you do to keep this information available.
> do you happen to have any service manuals for century data
> winchesters? i have a bunch of manuals for the removable drives
No, I do not. The only Century Data manuals I have are for the T-302,
which I believe you already have.
Alan Frisbie
Bill Gunshannon wrote:
>
> With 3.1 available why would you want to run 2.0? Someone mentioned
> a 4.0. I don't remember there ever being anything after 3.1 (promised,
> but never saw it delivered) Would be fun to look at. But I suspect
> anything beginning with 4 is actually Ultrix-32 which I think went as
> far as 4.5.
That seems likely, because AFAIR Ultrix-11 never got past 3.X.
In any way I would like to point out that Ultrix-11 and Ultrix-32 are
completely different: Ultrix-11 based on V7 (+addons) and Ultrix-32
based on 4.2BSD (+addons).
I actually still have Ultrix-32 3.1 running on a DECstation. It really
is nothing like running Ultrix-11 3.1, which I did many years ago.
Dennis
Hello,
For the sake of illustration to folks who are not necessarily used to
thinking about what computers do at the machine code level, I'm interested
in collecting examples of single instructions for any CPU architecture that
are unusually prolific in one way or another. This request is highly
underconstrained, so I have to rely on peoples' good taste to determine
what counts as "interesting" here. Perhaps a whole lot of different kinds
of work or lots of different resources accessed is what I'm after. I expect
these kinds of "busy" instructions were more common in architectures that
are now less common, so perhaps this list is a good place to ask.
For example, if we're thinking "number of times an item is retrieved from
RAM", then any application of the x86 string instructions that could walk
over memory for a while perhaps aren't so interesting. By contrast, by my
count, the NS32000 series instruction "addw ext(4), ext(7)" requires at
least five separate noncontiguous retrievals just to fetch the arguments
into the ALU. (Note that I'm not differentiating between different sizes of
data here: loading a 16-bit item and loading a 32-bit address both count as
a "retrieval" in this example.)
Instructions that are simply lengthy might be interesting, but not always:
long literals or lots of redundant prefixes on x86 aren't that impressive,
for example.
Number of registers read or modified might be good too, but just saving or
loading for the sake of subroutine calls (e.g. "movem.l r0-r7/a0-a6,-(sp)"
on the 68k) seems pretty pedestrian.
Other criteria may seem worthwhile; I trust peoples' judgement on this.
Although I don't know it well, I suspect VAX will place well in one way or
another. But to give an example of a candidate instruction that's prolific
in a way I find more noteworthy, I'll go back to the NS32k and offer
addw ext(4)+6[r1:w], ext(7)+12[r2:w]
which in order to get its arguments (I think) requires the five retrievals
already mentioned and adds two shifts and four additions to the bill. I
think this statement reads: "Add the r1'th word counting from 6 bytes past
the fourth address in the current module's link table to the r2'th word
counting from 12 bytes past the seventh address in the current module's
link table". That's a mouthful --- it takes a lot of work to describe what
that one line does! Maybe that's what I'm hoping to share with people.
I hope this is interesting to discuss,
--Tom
