Mainframe stuff...

From: Carlini, Antonio <Antonio.Carlini_at_riverstonenet.com>
Date: Thu Sep 20 05:04:23 2001

jkunz_at_unixag-kl.fh-kl.de wrote:

>There is the 8600 (aka 11/790) listed as a SBI machine.

That's correct. It was going to be known
as the VAX-11/790 until someone changed
their mind (it was very late, so they had
plenty of time to play with the name!).

>There is no reference to the 8700.

The VAX 8700 is a single processor VAX 8800.

>The 8800 is listed as:
> Basically an 8550 processor in a bigger box with space for
additional
> processors to make it into an 8820 or 8840

No. The Nautilus family started out as the
single processor VAX 8700 which could have
a few more (or many more, I forget) cards
added to become the dual processor VAX 8800.
The VAX 8550 was a VAX 8700 in a (big) cab
that could *not* be upgraded to a VAX 8800.
The VAX 8500 was a VAX 8550 with microcode
deliberately slugged to slow it down.
This was soon followed by a microcode update
that removed the NOPs ... *all* 8500s were
supposed to be upgraded and the machine
was renamed the VAX 8530.

The processor(s) live(d) on the NMI bus
(Nautilus Memory Interconnect, I assume).
The I/O bus was the VAXBI. This is in
contrast to the VAX 8200/8300 which came
out at the same time and used the
VAXBI as their system bus as well as
teh I/O bus.
 
>The 8550 is listed:
> XMI processor/memory backplane with VAXBI I/O

XMI is wrong ... it's NMI. The VAX 6000 series
was the first family (IIRC) to use the XMI.

>So I assume the "base" machine is the 8550. In a biger chasiss it is
>named 8700 and with a second CPU the 8700 is called 8800?

Yes, that's a good summary but
don't forget the runt of the litter,
the VAX 8500 (which rapidly became the
VAX 8530).

Antonio
Received on Thu Sep 20 2001 - 05:04:23 BST