🚀 go-pugleaf

Rainbow EchoMail Digest                                     Nov 22, 1990

In this issue:
  RE: MEMORY BOARD QUESTION
  RE: RAINBOW QUESTION


  Articles posted to either INFO-DEC-MICRO or comp.sys.dec.micro are
currently gatewayed to the Rainbow Echo on FidoNet. You do not need
to take special action to respond to articles in these digests.

  Please send reports of problems or suggestions for improvement of
this digest to GTHEALL@PENNDRLS.UPENN.EDU (Internet).
------------------------------------------------------------------------
Date:     11-16-90 (11:32)
To:       GEORGE THEALL
Subject:  RE: MEMORY BOARD QUESTION
From:     ANDREW TAYLOR

As I recall: the board with the banks of chips on it is a Rainbow 100B
memory board, which can be populated with 3 banks of 9 chips,
each bank either 64K or 256K.

The other board is a "retrofit" adapter board that DEC maide to allow
the 100B memory board to be put in the 100A: they used
basically the same design for their 8087 adapter board (for the
100A or 100B). I only installed one of them (though I have the
manual if needed..): I believe that you remove the 8086 from
the motherboard and plug the jumper cable into its socket.  The
adaptor board had an 8086 already on it, so you got a spare
8086 from the deal.

If you don't want the boards: one of our Club members asked me, 2 days
ago, about expanding the memory of his 100A

Andrew Taylor


- --- Opus-CBCS 1.12
 * Origin: Glacier Peak Rainbow, Bellevue, WA - 206/644-8431 (1:343/3.0)
------------------------------
Date:     11-19-90 (20:04)
To:       ALL
Subject:  RE: RAINBOW QUESTION
From:     FRANK ZSITVAY

In article <204.2743E4DE.@techbks1.FIDONET.ORG>
Paul.Robinson@f103.n109.z1.FIDONET.ORG (Paul Robinson) writes:
>Realize this:  IBM never patented the design of the IBM-PC, or the XT or the
>AT.  As a result, anyone could manufacture a competing machine if they could
>get a rom-bios for it.  And Phoenix, AMI, Award and - as Mike Focke's list of
>300 bioses shows - many others followed suit.

   the other bios companies started up because of the fallout of the apple
suit against the far east apple clone makers, who were selling clones of
the apple II+ with virtual copies of apple's rom.  by the time the ibm
pc was fair target for cloning, these apple clones were outlawed, and
it seems most manufacturers, even in the far east, learned that US copyright
law could be enforced.

   however, there is more to cloning than having a compatible bios, as
many purchasers of early clones found out.  the hardware port map and
memory map have to be the same.  if the hardware is the same, then you
could theoretically use, say, an ibm xt bios in a taiwan special xt.
however, i don't know if this works in practice, but it seems the major
project in producing an ibm compatible bios was to reproduce all of the
known features and bugs of the original, using a cleanroom approach.

>This meant that above all else a personal computer being sold for use in the
>IBM environment has to be IBM compatible or have a steep discount, and since
>computers are selling in the normal 5-10% profit range instead of the huge 30%
>to 50% profit figures of a few years ago, one has very little alternative but
>to make a compatible machine.  Such could have been guessed at because, given
>the choice between proprietary architecture and open architecture, people go
>for the open because they can get what they want from any supplier.

   true these days, but it wasn't always like that.

   there were some users who were scared away at the thought of having
to open their computer to install a board.  they would either pay a
service center an extraordinary price to do it, or they would buy a
machine that was not user expandable.  (so called 'Radio Shack architecture'
machines.)  in fact, some feel Radio Shack is to blame for this
philosophy, since you would void the warrenty on your trs-80 if you
openned the case.  this created a breed of hobbyist (users are another
matter altogether) that didn't care about hardware, and concentrated
on software.

>This behooves me to ask when the Rainbow came out; if they saw how badly TI
>was burned in both their small computers and in the PC market, they should
>have learned one thing: the open architecture is the way people want their
>systems, and will accept no less.  Trying to lock people in with a closed or
>proprietary architecture tends to lock you out of customers.  Yet they never
>learn.  Until Chapter 11, that is.

   DEC's idea for the rainbow was a little different from TI's idea for
the professional.  DEC saw the rainbow as superior to the IBM, and in some
ways they were right.  bear in mind, mainframe and minicomputer manufacturers
are very proprietary people, and if you owned a pdp11 or a vax, the only
thing you could connect to it was equipment the DEC approved of, which in
most cases was only DEC supplied hardware.  DEC originally scoffed at the
idea of the IBM PC, but when micros became popular, they decided they
would enter the market, but in their own way.

   Incidentally, DEC had what TI didn't have, which was a base of customers
who were loyal to DEC, as large IBM customers are loyal to IBM.  as such,
a lot of rainbow machines ended up in universities that had DEC mainframes
and minis.

   which really isn't so bad, when you consider that these machines tend
to lose value rapidly, which allows people like us to play with some
rather nice hardware.

   that is, unless it has the letters IBM on it...

- --
fzsitvay@techbook.COM - but don't quote me on that....
American Oil Company motto - Bend over, We'll pump!!!

- --- QM v1.00
 * Origin: TECHbooks One, Fido Gate to techbook (503) 644-8135 (1:105/369.0)
------------------------------