> 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.)
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!
Mainframes and other stuff
Recycle center in NC is willing to save out "stuff" for people.
No, no one can go in the back and scrounge.
No, he does not want a lot of emails from people.
Yes, he gets big blue and orange and beige 6 foot tall OLD mainframes in all
the time. They squash them at the moment.
Yes, he will package small orders, and will properly palletize larger
Local pick up will be available after the new year.
So, if u can send me a picture with description and some part numbers, along
with what you want to pay, I will consolidate things and make arrangements.
Please don't ask for specific boards from DEC; they don't want to go into
that much detail.
QBUS will mean nothing to him.
Big orange cabinet that says xxxxx is much more likely to get saved.
They are moving to new warehouse 1st of the month, so all this will start
happening after the 1st of the year.
1613 Water Street
Kerrville, TX 78028
sales at elecplus.com
AOL IM elcpls
About six months ago I struck a deal with a place down in California for
four Documation M1000's that I've been able to tell so far they all work but
I really don't have space for more than one. I've been trying to sell them
at a loss for months now over on the Vintage Computer Forums and Nekochan
(if you got here you'll find pictures) but no bites. I swear there were
people out there that were looking. Where did you folks go? Might anyone
here be interested? I absolutely refuse to put them on the curb.
I have a VAX730 with both TU58 drives destroyed (capstan melted, need
I also have a bunch of cassettes, but unfortunately all seem to have
problems with the bend and/or bad spots on the tape.
Possibly I would try to replace the broken bands (if I find a source)
and/or replace the magnetic tape when damaged (I was thinking to try
with audio cassette tape, don' t know if metal oxide high density tape
could be good for it).
Anybody has some information about the coercivity of original DEC TU58 tape?
One problem indeed is the need of reformatting the tape, but: if I can
emulate the TU58 drive using a serial, would it be possible to send
raw commands to the drive using the serial and a PC?
PS-If possible, some good-condition cassette would be very useful to
me too. I'm located in Italy.
> From: Eric Smith
> which would respond to ARP requests for non-local addresses and reply
> with the router's MAC address (on that interface), specifically in
> order to make classful-only hosts work on a CIDR network.
Yeah, Proxy ARP (an early RFC here:
but IIRC it was people at CMU who first came up with the idea; this RFC is
>from people at UT-Austin, documenting it) was originally done to support
for more) when it was first introduced - for hosts for which people didn't
have the source, but needed to attach it to a subnetted network.
Subnetting was a stage before CIDR (which took subnetting and Carl-Herbert
Rokitansky's 'supernetting' and mushed them together).