10 Feb
2013
10 Feb
'13
5:57 p.m.
On Fri, 8 Feb 2013 13:15:50 -0500 Ethan Dicks wrote:
On Fri, Feb 8, 2013 at 1:03 PM, Dave McGuire
<mcguire at neurotica.com> wrote:
I got v1 running on my 11/20 about a year and a half ago. I bolted a
Nexys2 board onto a quad-height wire-wrap board with Unibus transceivers
and a bunch of latches/buffers to handle the 5V/3.3V level shifting (as
well as to mux the large number of Unibus signals to/from the Nexys2).
The code in the Xilinx has 4MB of Unibus memory, RF11, RK11/RK05, KE11-A,
KW11L, as well as other Unibus peripherals. The on-board flash contains
the bootstraps, initial loads for various software images, and multiple RF11
and RK05 images.
It ran on my real 11/20 and a real KL11, but all of the other peripherals
were emulated on the board. I took some pictures of it running with an
ASR 33 for the editors of an IEEE article, but the pictures probably weren't
interesting enough and didn't make it into the article.
One of these years, I'll get around to running using a real KE11-A, RK05,
TU56, and PC05. I also have a 3rd party RF11-compatible disk, though
running that is a long-shot, so the RF11 will probably remain the one
emulated peripheral.
On a side note ... the Xilinx also contains a full PDP-11 CPU, so the whole
thing can even run standalone. One of the peripheral emulators in it is for
the graphic processor used in the Galaxy Game. This got hooked up inside
an original Galaxy Game cabinet with original joysticks for use at the
California Extreme video game event last summer (the Galaxy Game cabinet
with the original PDP-11/15 in it is running at the CHM).
In fact, the original purpose of the Nexys2 code was to convert the vector
graphics output from the Galaxy Game into a frame buffer to drive an SXGA
compatible monitor. The scope of the code in the Xilinx kind of grew from
there and I still end up adding things into it every six months or so.
James Markevitch
I *think* I have a couple KE11-B boards here.
(Sadly no compatible
machines to put them in.) I'll go check if you like; let me know.
You can put me on the list of interested parties. I am about to move
my 11/20 from long-term storage to a place where I can work on it - it
needs *lots* of restoration work since I recovered it from a dumpster,
literally, and one of my goals is to try to get v1 UNIX running on it
(which requires a KE11).
I'm not in a hurry - I still have to repair lots of things and I have
to come up with a way to replace the RS11 swap disk that UNIX is
expecting, but once I get the CPU restored and the external memory
cabinets fixed up and powered (and a missing core plane replaced), I
can turn to diagnosing and repairing my RK11C, *then* I'll be in a
place to worry about a small, fast swap disk.