[HECnet] PDP Ignorance

[Steve Davidson]

Mark,

Rare - probably depends on where you can look! :-) 

RT-11 will run on any of the PDP-11's.   The RSX-11 family of OS's has
specific requirements about memory amounts and memory management thus
the SPD should be reviewed.   RSTS/E (and M+) require memory management
hardware.   If you can find one, the best is probably the 11/73, 11/83 or
11/93 in a BA23 (QBUS) enclosure.   These come in either 4, or 8-slot
backplanes.   If you really want to experience pain in your electric bill
then the BA123 (also QBUS) with it's 645 watt dual power supplies can
double as a winter heater/loud white-noise generator.   These come in a
12 slot backplane configuration.

The Pro-Series of systems could also be looked at for RT-11 and RSX
(P/OS).   In this space the Pro-380 is probably preferred.   The problem
here is finding a network card (DECNA) that does not cost as much (or
more) than the rest of the system.

Disks on real hardware will be small and slow (an possibly expensive).
On emulated systems they can be much bigger and many many times faster.

The books you have detail the degree of expandability for each of these
HW platforms (except maybe the Pro).   You will be surprised at just how
much can be done with these systems.   The speed will be another story.

All of these machines have some weight to them.   An emulator will be
much faster and in the end easier to deal with.   When the PLUTO::
machine is running as an emulated machine it is running with NetBSD and
SimH on a 700MHz Pentium-III, otherwise it is a real PDP-11/23+ (22-bit
backplane).   The emulated machine is faster than the real thing, but not
my much.   I was going for similar performance so that when I switch
between the two it wasn't that noticeable/painful to return to the
actual hardware.

PLUTO:: configuration (from memory)
  BA23 backplane (8-slot version)
  PDP-11/23+
  4MB memory
  FPU chip set (somewhat rare these days)
  CIS chip set (extremely rare these days)
  2 * RQDX3 controllers - 1 for RD54 and dual RX50 drives (internal) and
1 for RD5x drive (external)
  KLESI controller (TK50 tape drive (external)
  DELQA NIC
  2 serial ports (on main CPU board)
  4 serial ports (on DHQ11 board)

RT-11 Languages (from memory):
  MACRO-11
  APL-11
  BASIC-11
  MU/BASIC-11
  BASIC-PLUS/RT-11
  FORTRAN-IV (FORTRAN 66 STD)
  PDP-11/C
  DECUS-C

RSX-11 Languages (also from memory):
  MACRO-11
  APL-11
  BASIC-PLUS-2
  FORTRAN-IV (FORTRAN 66 STD)
  FORTRAN-77
  PDP-11/C
  DECUS-C
  COBOL-81, COBOL-11

RSTS/E Languages (also from memory):
  The same as RSX-11 for the most part.

If you want to have a look around RSTS/E,   I can create an account on
PLUTO:: for you to poke around.   Just let me know off-list.

-Steve

-----Original Message-----
From: owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE] On
Behalf Of Mark Wickens
Sent: Thursday, July 14, 2011 15:50
To: hecnet at Update.UU.SE
Subject: Re: [HECnet] PDP Ignorance

Are the MicroPDPs (desktop, deskside, rackmount) rare beasts? They seem
to be of a fairly hobbyist-friendly size, although presumably they are
less expandable (much like a VAXstation versus VAXserver I would
imagine)

Mark.