[HECnet] Raspberry Pi + SIMH VAX?

[Sampsa Laine]

I configured a Linux box to automatically fire up VirtualBox from rc.local, and then run a stripped down Linux instance in the VM to run SIMH-VAX.

Point being that I could then access the network interface of the SIMH-VAX from the host running VirtualBox :)

The host also ran decnet-linux..

It was quite nifty, but too heavy-weight for a Pi..

Sampsa


On 4 Jun 2012, at 03:06, Boyanich, Alastair wrote:

Hi Rob,

There may be a super easy way. Try the /etc/rc.local script file. You
can think of it in old MS-DOS/Amiga terms as the AUTOEXEC.BAT or
S:user-startup files. This script usually gets run after the system has
entered muti-user mode and after the networking is up and running. Have
a go running your simh VAX executable from there :)

You can also get fancy with GNU Screen so that it saves and disconnects
the console so you can connect to it after an auto-startup.

Regards,
Al Boyanich

-----Original Message-----
From: owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE] On
Behalf Of Rob Jarratt
Sent: Monday, 4 June 2012 9:45 AM
To: hecnet at Update.UU.SE
Subject: RE: [HECnet] Raspberry Pi + SIMH VAX?

I got my Raspberry Pi a few days ago too. I too have had few problems,
although for some reason the download of libpcap took an extraordinary
amount of time. I have built the 780 emulation, along with two
modifications
of my own, difference disk files, and a DMC11 emulation.

I am running the Pi now 24 hours a day as my HECnet router (node
VAX780 at
5.8) using the bridge running on a server that I already run 24 hours
a day.
The virtual disk files are stored on the server and I use SMB to
access them
from the Raspberry Pi, partly because the 8GB SD card I planned to use
did
not work and I had to use a 4GB one, partly because I have heard that
SD
performance is poor.

I am not as good on unix these days as I used to be, is there an easy
way to
get SIMH to start up automatically on booting the Pi?

I like the idea of a cluster of Pis, might get a few more at some
point and
try that myself.

Regards

Rob

-----Original Message-----
From: owner-hecnet at Update.UU.SE [mailto:owner-
hecnet at Update.UU.SE] On Behalf Of Mark Benson
Sent: 03 June 2012 22:21
To: hecnet at Update.UU.SE
Subject: Re: [HECnet] Raspberry Pi + SIMH VAX?


On 4 May 2012, at 00:07, Boyanich, Alastair wrote:


Sampsa:

Interesting. Be sure to set up the idle detection in the simh.ini
for
your appropriate OS (netbsd/TheoLinux/VMS/Ultrix/etc..) or it'll
run
the CPU flat-out all the time and potentially get hot. I'm really
curious to hear how 'hot' the R-Pi's get under load. Mine's still
on
order.
Beautiful idea.

I got my Raspsberry Pi Thursday. It runs SimH 3.9.0 flawlessly under
the
provided Debian Linux 'squeeze' distribution from a SD Card. The I/O
on
the
RPi isn't fantastic from SD Card, it just about manages 5.5MB/s by
most
people's benchmarks which is rather slow.

libpcap and screen are installable from the provided arm6l
repositories so
no
need for compiling those. Once I did that I just downloaded the
source
zip,
unzipped it into a directory and used 'make' to build, just like
normal.
Built
fine and runs perfectly.

PDP-11 simulation is plenty snappy enough running RSX-11M Plus 4.2
on a
simulated 11/83 with 2048kW of RAM. I have DECNet 4.0 (Phase IV)
working
on there too and it works fine.

VAX KA655X simulation is... sluggish. I'm used to running it on
1.xGHz
x86_64
CPUs (Atom or AMD) with fast hard drives or SATA SSD. The CPU speed
makes it slow but imagine it's as fast or faster than a real late
model
VAX. It's
by no means perishingly annoying, it just takes a little thinking
between
operations. I think I may be spoilt as I've never used a real VAX.

Overall so far I'm very impressed with the RasPi and it will fulfil
the
roles I
need for it. When I get hold of a few more I am going to try and
build a
VMS
cluster that uses less than 6W :) I will also have one permanently
running
a
PDP-11 (something that I've not managed since I had my Cobalt Qube2
running) RSX-11MP system.

Oh and CPU Idle works just fine in PDP-11 and VMS-VAX simulations.
To be
honest even when I compiled all the simulator binaries for SimH (as
a
stress
test) and when I was running the SYSGEN in RSX-11M it barely got
much
worse temperature-wise than hot to touch a the CPU. On a board that
only
uses 300mA with no USB and Ethernet active it hardly has a lot of
energy
to
dissipate as heat in the first place!

I'm gonna have a LOT of fun with these :D

--

Mark Benson

http://DECtec.info
Twitter: @DECtecInfo
HECnet: STAR69::MARK

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