LSI-11 question

From: Megan <>
Date: Fri Mar 19 22:41:15 1999

Jerome Fine replies:

>What was a GT40?

It was an 11/05 system with an integral VT11 display processor
and a second serial line all mounted in one of the 5.25" high
chassis. It had a typical pdp-11/05 front panel, but the
color of the silk screening was green and some other color...
The chassis had side rails that a VR14 vector graphics display
could slide into above the system chassis. The unit has a keyboard
and a light pen. The ROM has code to provide a very dumb
terminal... it was generally attached to a decsystem-10 which
could down-line load code into it for execution.

>I was asked recently to comment on a system
>which originally used a VT05 and then a VT52. I actually kept a
>working VT52. What was a VT05? Or at least what were the
>differences between a VT05 and a VT52?

The VT05 is the earliest of the 'glass tty' terminals that I
remember... I first saw one at a DECUS in Boston around 1973
or so. It was long and angular. I've never seen a programming
manual for one, so I don't know if it even supported escape

>Incidentally, get a VT103. The standard memory size is 256 KBytes
>and if you re-wire the backplane, you can have all 4 MBytes.

>As far as I know, the RT11SJ in V5.4G required about 4800 bytes
>plus about 4100 bytes for the USR and something (about 500)
>for the device driver. That would leave only about 6 KBytes for
>the user job, probably not enough. Maybe the utilities are designed
>to work without the USR being there all the time and RT11SJ might

That's right... systems typically ran with USR set SWAP. Back
then we jokingly had a standard response to any problems which
came in... "SET USR NOSWAP"...

>Also, as far as I know, the VT11 support was still present in V5.4G
>of RT-11.

VT11 support is still in the VTHDLR library file, but I think that
the GT ON/GT OFF commands were removed much earlier than that...
I don't know if EDIT lost its VT11 support... same thing for TECO.

>Mentec has access to V5.3 of RT-11. Actually, everyone who wants
>to run V5.3 of RT-11 under a hobby license with the Supnik emulator
>can download V5.3 from gatekeeper. Megan Gentry made V5.3
>available (or was very instrumental in doing so - thanks Megan)
>some time ago. Do you want the URL?

I have other releases prior to V5.3... I've been thinking of trying
to get them packaged up to be made available -- in my 'copious free
time' (tm)

>P.S. Megan - have a good PDP-8 pickup and don't strain
>yourself. That is real heavy iron.

I know... two H960s and one 4' rack... with 4 pdp-8s and disks,
tapes, etc... and an 11/34 with LPS, VT11 and VR14...

Lots of *Iron*... I certainly won't be anemic for some time... :-)

but it still looks like I'll be going it alone (unless I hear from
my son)...

                                        Megan Gentry
                                        Former RT-11 Developer

| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry! |
| Unix Support Engineering Group | (home): mbg! |
| Compaq Computer Corporation | addresses need '_at_' in place of '!' |
| 110 Spitbrook Rd. ZK03-2/T43 | URL: |
| Nashua, NH 03062 | "pdp-11 programmer - some assembler |
| (603) 884 1055 | required." - mbg |
Received on Fri Mar 19 1999 - 22:41:15 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:32:21 BST