----- Original Message -----
From: Timothe Litt
To: [email protected]
Sent: Thursday, July 20, 2017 12:06 PM
Subject: Re: [Simh] Rainbow100
On 19-Jul-17 23:23, Bill Cunningham wrote:
There's no simulator for DEC's first micro is there? Will there ever be
one?
Bill
That wouldn't be the Rainbow.
There was the Harris/Intersil pdp-8 on a chip c.a 1975.
The DEC/WD LSI11 c.a. 1976 followed.
All these were in embedded systems. The LSI-11 (and especially its
follow-ons, the T/F/J11) were used in a number of DEC's storage and
communications controllers, until ultimately replaced by VAXes. (Yes, your VAX
probably had more VAXes in the IO subsystem than you knew about.) They were
also very popular for third party embedded systems - from volume copiers to
airport landing lights.
If by 'micro', you mean general purpose consumer packaged Intel architecture
machine, that would be the Robin (VT180), which is a Z80 CPU with dual 5 1/4
inch floppies, as a plugin board for the VT100. CP/M. Produced in the AD
group, which Bob Glorioso managed at the time. Released c.a. 1982. The board
had its origin as a model railroad controller created as a hobby project by an
engineer in that group, and was brought in and adapted for the VT180 as a quick
time-to-market product. (I subsequently subsequently re-adapted the board for
something completely different - and learned the history a few years later.)
The VT103 used the same idea, but with an LSI-11 backplane and T11 - TU58
tapes & RT11. But it was later, and not on the IA path.
The Rainbow was the replacement for the VT180 (c.a. late 82/early 83), used
RX50 diskettes and optionally, a st506 winchester drive. It was part of the
triplet of machines, which also included the Pro 350 (pdp11) and DECmate
(PDP-8), that Ken Olsen pushed as the answer to the "cheap, poorly engineered"
IBM PC. Besides being over-designed for the market, all three suffered from
being closed systems with hardware architectures different enough from the
standards (IBM PC/QBus/Omibus) to disable commodity software. Especially the
Pro350, with its lobotomized P/OS operating system (RSX with a horrible GUI)
and limited menu of application software. (Eventually, RT was released, but
too little, to late.) The DECmate never pretended to be anything other than a
word processor. Ken's belief that quality would overcome price in this market
turned out to be very wrong. And locking out existing software made them niche
products.
Both the Rainbow and Pro got minor upgrades, then died. The DECmate was the
most successful of the three in that it did exactly what it set out to do; no
more and no less. It got larger winchester drives and some minor software
updates, but basically kept chugging along until technology - Apple,
WordPerfect (and eventually Word) - provided bitmapped fonts. (But lost the
gold-key UI in favor of the mouse...)
I don't think there was any real volume for the PC devices until the
DECstation IBM PC compatibles came along, which IIRC were undistinguished Tandy
buy-outs.
And yes, the Z80 is a superset of the the Intel 8080, so perhaps you can
argue that it's not strictly IA. But the Rainbow included one (you could run
CP/M on it, and it served as an I/O controller for the 8088). And in any case,
the VT180 fit the common definition of "micro" at the time.
In any case, by no definition was the Rainbow "DEC's first micro".
Ok go that from www.livingcomputers.org
Bill
_______________________________________________
Simh mailing list
[email protected]
http://mailman.trailing-edge.com/mailman/listinfo/simh
