> From: Mattis Lind
> Thanks Noel for sorting this out.
Eh, de nada. But thank you.
>> I wonder if the ucode in the two versions is identical? The uROM chip
>> numbers should give it, (if they are the same on both versions, albeit
>> in different locations on the board), but I have yet to check. Does
>> anyone happen to know?
OK, so the situation here is pretty complicated. To start with / make things
worse, that CPU uses lots of PROMs. Lots and lots and lots and lots of PROMs.
For the data paths board (M7260), both major versions appear to contain the
same PROMs (going by the DEC part numbers), but the chip location (Exx)
numbers are all different.
For the control board (M7261), the C, E ('early' version) and F ('late'
version) etch revisions each contain mostly the same PROMs, but apparently
with slight differences between the sets of PROMs in each (as reflected in
different DEC part numbers). For details see:
to which I have just added all the gory details.
As to getting the contents of all of them dumped in machine-readable form -
>> on the earlier version (prints for that version are in the GT40 prints
It turns out that I have hard-copy prints for the "C" etch revision of the
M7261, which do not yet appear to be online; the GT40 prints have the "E"
I will scan the pages for that revision of the board, and put them up 'soon'.
(I'm not doing the whole print set, it's about 1" thick, and most of them are
for other things anyway, like MM11-L memory, etc.)
> From: Toby Thain
> To get closer I'd need better images of the panels.
Hi, I borrowed a DEC inlay from someone (a KA10 CPU bay) and scanned a chunk
of it (as much as I could fit into my A4 scanner :-) at 200 dpi:
I have a TC08 inlay, but it's currently being used in my QSIC display (until
we can get the RKV11-F/RPV11-D inlay done :-), and I didn't want to yank it
out. As far as I can tell, it's the same font on the two of them.
> the closest I know of off the top of my head is Akzidenz Grotesk.
The Akzidenz Grotesk Medium is indeed very, very close (other than the zero).
Do you happen to know if that font available for use in non-commercial
Since a few days, my EXORciser Development System is finally able to boot from floppy diskettes.
Previous attempts have shown that the Motorola EXORciser M68SFDC1 floppy disk board used has a special modified ROM version. This was probably written for an 8-inch drive, in which the Write protect and Direction signal were inverted.
For the sake of simplicity, I have used free inverter on the board to invert the signals accordingly.
After adjusting the PLL frequency, reads and writes from the card are now error-free. And all without FDC, only clever programming by Motorola software engineers in the early 76?
Originally, the EXORdisk system was a dual drive with two 8 "units. This I have replaced with a double drive of two 5.25 inch units. An Epson and a TEAC, which can be jumpered to 360 rpm. Luckily, 2HD floppy disks are easy to R&W.
I also got a GOTEK floppy emulator running, which I can boot from. Thanks to Roland Huisman, Bitsaver has some interesting floppy disks that convert to HFE format work perfectly. This format makes the Gotek drive most reliable.
Now to my question. The vintage computer forum at http://www.vcfed.org/forum/archive/index.php/t-44638.html mentioned some interesting manuals. Archive.org has some manuals, Bitsaver does not have manuals about the M6800 development system.
If someone already owns scanned manuals to the following list
M6800 Basic Interpreter Reference Manual
M6800 Macro Assembler reference Manual
M68SFDU Exordisk 11/111 Disk `Drive Unit Maintenance Manual
M6800 Exorciser 11 User's Guide
M6800 Exorciser User's Guide
MEX68PP1 PROM Programmer Module Supplement M6800 Exorciser User's Guide
I would welcome any feedback or questions
The famous Brigham Young University 3D graphics program, by Dr. Hank Christensen.
I am looking for the fortran source, it should be 7 files:
Any docs related too.
Thanks for letting me beg.
Hi all --
I picked this DPS-6 up over the summer and it's just taking up space
(quite a bit of space) in the corner of my basement. This is a custom
16-bit, bitsliced, microcoded CPU from the early 80s with (I believe)
8mb of memory, and ethernet. It would originally have run a version of
GCOS. It's about the size of a large-ish minifridge, but a bit deeper.
It's also quite heavy!
It's a neat machine, but it's very obscure and unfortunately incomplete
(it is missing both mass storage and storage controllers). Otherwise,
it is complete and in good condition (albeit a bit dirty). So you can
see why you'd really want to have it in your collection .
If anyone's up for a project, drop me a line. Local pick up in Seattle, WA.
This is listed under the informative title "vintage computer":
which leads me to post it here under a more informative title, hoping that
someone here has a soft spot for Primes!
Ok. Those are quite small. So you have one? Or those are not yours?
If you have one, and a way to accurately measure it, making more will be easy for anyone with a lathe.
I could do it, but surely you can find a machinist closer to home?
At 01:03 PM 10/11/2018 +0000, Riesen Thomas wrote:
>I am looking for small motor pulley ... see pic ...
>Von: Guy Dunphy [mailto:guykd at optusnet.com.au]
>Gesendet: Samstag, 10. November 2018 13:25
>An: Riesen Thomas <thomas.riesen at predata.ch>; General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>Betreff: Re: 50Hz Pulley for 8" Floppy Drive Mitshubishi M2894-63B
>At 12:03 PM 10/11/2018 +0000, you wrote:
>>Any suggestions where to find two 50Hz-Pulleys for the 8" Floppy drive
>>If there also the appropriate ribbon gummies available, I would be very
>Do you know what they look like, and the dimensions?
>Because I have these. http://everist.org/pics/misc/IMG_1655_pulley_800.jpg
>_Maybe_ they were off Mitsubishi drives, not sure. Had them in a box of floppy drive related bits for a loooong time, and have no recollection of where they came from.
>These are 49.0 mm OD, hole 4.7 mm dia. And this is Australia, with 50Hz mains.
>Attachment Converted: "f:\email\attach\Pully_8Zoll_02.jpg"
>Attachment Converted: "f:\email\attach\Pully_8Zoll_01.jpg"
We found a PDP-11 QBUS card cage with a KDF11 and some other cards (RAM,
ROM, some basic peripherals) which included a DSD-4140 card.
Unfortunately, the DSD-4140 is missing one of it's microcode PROMs for
Does anyone else have one of these cards? It'd be really helpful if we
could get some dumps of the 4 microcode PROMs so we can compare what we
have and look into replacing what we don't have with an adapted modern
part. (and if anyone goes to the trouble to read the 4 microcode PROMs,
there's also an 82S137 that deserves to be dumped).
Here's a picture of the card in question: https://i.imgur.com/tzYjPYF.jpg