9 May
2012
9 May
'12
1:54 p.m.
From: Ethan Dicks
Sent: Tuesday, May 08, 2012 10:08 PM
On Tue, May 8, 2012 at 11:27 PM, B Degnan <billdeg at degnanco.com> wrote:
> More photos from VCF East 8
> http://vintagecomputer.net/browse_thread.cfm?id=466
You wrote:
"Mike Ross' exhibit consisted of a PDP
11/05 used to interface with
a PDP 15, in two racks. He demonstrated restoration techniques for
attendees. I am not sure exactly what you call this console, there is
no "PDP 15" on the panel, but I assume it's some kind of I/O device
that complements the (not pictured) PDP 11/05 used to presumably
bootstrap this thing."
That _is_ the PDP-15 front panel - if you look, there
are 18 data
bits. The PDP-15 CPU was the large spread of M-series cards on the
backplane above this front panel. Its memory was in a black box below
(and not there for much of the weekend). The PDP-11/05 is
self-contained and does the same job as the PDP-11/03 in a VAX-11/780
or the PDP-11 in various models of PDP-10. In each case, the PDP-11
boots from its own ROMs to start up enough code to feed the larger
processor. In the case of the VAX-11/780, the PDP-11/03 has one RX01
floppy drive. I don't know what this PDP-11 uses, but there must be
some local mass storage that's part of the scheme.
Only the KL-10 uses an 11/40 as a boot processor like the 11/03 in a
780. The KS-10 uses an 8080, and earlier models booted directly from
paper tape or DECtape; it's not clear to me yet whether a KI-10 could
boot directly from disk, but I tend to doubt it based on what I'm seeing
in ours.
Rich Alderson
Vintage Computing Sr. Systems Engineer
Vulcan, Inc.
505 5th Avenue S, Suite 900
Seattle, WA 98104
mailto:RichA at vulcan.com
mailto:RichA at LivingComputerMuseum.org
http://www.LivingComputerMuseum.org/