Hi !

On Tue, 27 Feb 2001, BrownM03 wrote:
> 1. Michael
> > BTW: If you are new to VAXen... don't confuse SCSI and DSSI on you 100, or
> you
> > could trash this fantastic machine... It's a quite nice beast in
> performance!
> OK, what is the difference between DSSI & SCSI connectors?

Ehm, internally none, they just look the same. That's the reason for my
warnung :) In my 105A, the DSSI cables go to some little option board in the
right side of the machine, it has 2 buses. SCSI goes directly to the main
board. The power connectors can't be confused, they are different.
Externally, DSSI and SCSI differs by the gender (SCSI is female, DSSI is male,
looked into the HD D-Sub connector), But DSSI can also be a small Centronics-
like connector.

> Would it be fair to assume that devices with 5pin power plugs are DSSI?

Yep. But they can be mixed-mode. I think i have such a 1Gig DSSI/SCSI disk in
my 105. If the model number starts with "RF", it is DSSI, "RZ" is SCSI. And if
it has one "RF" and one "RZ" number, as my disk has... you know, what i mean.

> Or am I grabbing at straws there?
> Fantastic? (I would agree ... but probably mostly from ignorance), what
> makes this
> box so good? I've not been able to find much documentation on it.

a) It's A VAX!
b) It's no Intel :)
c) It's the godfather of CISC-architecture
d) It's the first CPU knowing of virtual memory (i think), that's where the
   name comes from: Virtual Address eXtension.

Ok, seen in numbers, this machine has the performance of about a P75, compared
to an Intel. Maybe this is even true in single user operation. But plug in
500 terminals to a P75 and a VAX of the same memory/disk configuration.
The P75 will get extremely slow, but the VAX shows it's real capabilities, they
are mainframe-like in I/O and multiuser operation. The 105A i have (just a bit
faster than your 100) was capable to service over 1000 people, and was in that
use up to 1999 or so. Show me an intel-machine beating this :)

So: Don't expect to run quake on this machine, it simply isn't build for such
purposes. My 105A here runs sendmail, imapd, fetchmail, squid, apache with php
and ssl, mysql client, and lots of other nice things not needing pure CPU
performance. And it works _VERY_ nice for this job.

> That would be great thanks Michael, my only net-connected machine (at the
> moment)
> is a W2K box, and all attempts to connect to
> ftp://ftp.unixiron.homeip.net/NetBSD-vax-1.5
> fail on the LIST command. (I've tried IE,command line & CuteFTP)

Argh, ok, this is a passive/active problem. You'll get a mail with the kernel
i use here. (Ragge, is your last work for the 105 somewhere publically
reachable?). Don't wonder of netstat/ps/iostat problems, this kernel doesn't
match the 1.5 userland... You could rebuild the whole userland or look out for
a complete -current snapshot in binary.

> 5. Every(any)one :)
> ANY information about 4000-100 vaxen, DSSI, Q-BUS, etc... would be handy.
> Including info on the external ports; ie. what they are and how I can use
> them.

Have a look at vaxarchive.org and the links there to learn a lot of VAX basics,
then look at the rear of your machine. If it is nearly the same as my 105, you
should have 3 serial ports (MMJ connectors), port 3 is the serial console.
You should also have 3 DSSI connectors, 2 are for the same bus (0). At least
the left side of bus 0 should be terminated. The 2 50pin DSub-connectors
between the DSSI connectors are for connectin an external QBus box to use the
nice cards usually made for the "bigger" VAXen. Usually, the 4000 is one of the
"bigger" VAXen (ok, it is very small compared to the most other VAXen :) and
have an internal QBus. But as the 10x series has DSSI, SCSI and such things
on the mainboard, and enough space for some drived, DEC might have thought,
they just don't need a QBus on every machine and made it external this way.
Ah yes, you also have a serial port with a usual 25pin DSub connector, this
is port 2 (MMJ are 0, 1 and 3).
Then you find AUI and Cheapernet connectors and a switch to select between
them, a HALT button, some diag LEDs and a strange switch, which looks a bit
like S3 on VAXstations to select serial/framebuffer console, but the VAX
series just don't have famebuffers...

> ps. do you guys prefer short messages? :))
> (yes I'm new to mailing lists as well:)

Not a bad idea... pivate threads should stay private, and the thread over the
list should be kept not too long... But it's ok, you didn't go that wrong
here, as the 10x series could really be of public interest, the machines get
available more and more.

...Michael

-- 
In TV, there are bluescreens to put a faked reality behind a real played scene,
in Windows, you sometimes see the real scene, when the fakes go out for lunch.