VAXstation 3100/M76 specific notes
Currently I own two of them. The first one came via eBay auction from another
collector liquidating his DEC collection. I hoped I would get a fast box
to run ULTRIX/VAX, but, silly me, I had to learn that ULTRIX won't run on anything
as new or newer than an VS3176 :-(
Strangely enough, the machine's console mentions ULTRIX as an option to boot.
This leaves pretty much VMS as the only OS option, unless the *BSD
people get their act together and fully support the GPX/SPX graphic boards.
In 2006 or 2007 I got a second VS3176 for free from a hospital nearby.
As everywhere else, the last pieces of DEC equipment are
being phased out. Until the early 1990s, DEC VAXen and Alphas running VMS were quite abundant
in technical computing, such as radiotherapy and radiodiagnostics.
Since I work in that field,
I still have computer tomographic data sets marked "VMS byte order" by their creators,
which was sloppy language for "little endian".
("Big endian" was marked "AIX byte order", btw).
I have some hope I might recover more such DEC boxes before they go to the scrap yard.
Anyway, the second VS3176 came without video board, so I implanted an SPX
which I had removed from an M30.
Pixx
Gfx issues
The VS3100 supports GPX and SPX video boards.
Even without such a board
some onboard monochrome gfx is possible
(output on pin 9 and ground on pin 3).
A special DB15-single BNC adapter (BC23J-03) is required.
To get gfx support, the
S3-switch on the rear side must be in "down" position.
Console startup issues
Console startup takes quite a long time,
in particular memory test (F..E..D..C..B) may take minutes - be patient.
In case of malfunctioning or non-existent video subsystem,
it is possible to startup via the "alternate console".
Put the S3 switch,
located on the rear side between the MMJ serial line outlets and the status LEDs,
in upward position
(don't use pencils with graphite contents !)
and connect the MMJ printer (!) outlet with the serial port
of a computer acting as a console device.
For this purpose I use an Amiga 1200 with the
Kermit terminal program.
Serial line Parameters are: 9600 baud, 8N1, XOn/Off.
Change controller's SCSI ID
By default, the SCSI controller has ID=6
(ID=7 being reserved for higher priority tasks).
To change that, if so desired, at the console
set scsi 7
Bootable CD-ROM
Seemingly,
does not boot from external
Plextor PX-32TSi. Use an RRD40 instead.
Memory
A VS3100/M76 can take 8x4MB = 32MB of special 80-pin memory parts.
The 16MB parts from the VAXstation 4000 line will work, but only
4MB will be recognized.
The memory slots have to be populated "columnwise", i.e. one bank first,
then the other one.
Maxtor HDs
Maxtor MXT-540S disks (extracted from ancient IBM RS/6000 25Ts)
with VMS system clones were bootable.
ULTRIX support
A VS3176 doesn't run ULTRIX,
the console messages are misleading.
Last updated: 16-Nov-2008, M.Kraemer
