23 Apr
2007
23 Apr
'07
10:39 a.m.
-------------- Original message ----------------------
From: cctalk-request at classiccmp.org
3. Re: Lack of 8-bit threads (was Re: Linux
question) (Chuck Guzis)
Message: 3
Date: Sun, 22 Apr 2007 08:50:00 -0700
From: "Chuck Guzis" <cclist at sydex.com>
Subject: Re: Lack of 8-bit threads (was Re: Linux question)
One other fairly popular "nearly compatible" that I recall is the
Mitsubishi PC. Like the Convergent-designed 6300 It was a headache
for a lot of applications. Not really inferior to the 5150, but
different enough to be frustrating.
The 6300 (and 6300 Plus) were designed and built by Olivetti, probably by the same
engineers who used to keep Mussolini's trains running on time. Their DB-25 video
connector is the only reliable way ever discovered to break a Radio Shack Daisy Wheel
Printer II (aside from tossing the beast into a smelter). Convergent did the 7300 and 3B1
Unix PCs (vastly superior machines in my arrogant opinion, but I'm partial to just
about any MC68k series systems that didn't come from Cupertino).
--
Ward Griffiths wdg3rd at comcast.net
The reason folks don't think of installing Windows as a painful experience is roughly
the same reason men don't think of childbirth as a painful experience. Mike,
http://www.theregister.co.uk/2007/03/30/letters_3003/
24 Apr
24 Apr
11:55 p.m.
wdg3rd at comcast.net wrote:
The 6300 (and 6300 Plus) were designed and built by
Olivetti, probably by the same engineers who used to keep Mussolini's trains running
on time. Their DB-25 video connector is the only reliable way ever discovered to break a
Radio Shack Daisy Wheel Printer II (aside from tossing the beast into a smelter).
Convergent did the 7300 and 3B1 Unix PCs (vastly superior machines in my arrogant opinion,
but I'm partial to just about any MC68k series systems that didn't come from
Cupertino).
I don't understand the line about the db25 monitor connector being able
to break a printer. Could you explain?
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Help our electronic games project: http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
A child borne of the home computer wars: http://trixter.wordpress.com/
25 Apr
25 Apr
7:25 a.m.
On Tue, 24 Apr 2007, Jim Leonard wrote:
wdg3rd at comcast.net wrote:
If memory serves, the monochrome monitor on the 6300 was powered from
15V on two pins on the DB25 female connector on the video card.
Plugging your parallel printer cable into the video card would do nasty
things to the printer.
Mike Loewen mloewen at cpumagic.scol.pa.us
Old Technology http://sturgeon.css.psu.edu/~mloewen/Oldtech/
The 6300 (and 6300 Plus) were designed and built
by Olivetti, probably by
the same engineers who used to keep Mussolini's trains running on time.
Their DB-25 video connector is the only reliable way ever discovered to
break a Radio Shack Daisy Wheel Printer II (aside from tossing the beast
into a smelter). Convergent did the 7300 and 3B1 Unix PCs (vastly superior
machines in my arrogant opinion, but I'm partial to just about any MC68k
series systems that didn't come from Cupertino).
I don't understand the line about the db25 monitor connector being able to
break a printer. Could you explain?
2:32 p.m.
Mike Loewen wrote:
Ah, I forgot that the monitor was female. Yes, a mistake like that
would most likely make a peripheral go poof.
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Help our electronic games project: http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
A child borne of the home computer wars: http://trixter.wordpress.com/
I don't
understand the line about the db25 monitor connector being
able to break a printer. Could you explain?
If memory serves, the monochrome monitor on the 6300 was powered from
15V on two pins on the DB25 female connector on the video card. Plugging
your parallel printer cable into the video card would do nasty things to
the printer. 
5:40 p.m.
Jim Leonard wrote:
wdg3rd at comcast.net wrote:
The monitor connector on the Olivetti M24 and the ATT 6300 was a
25-pin "D" connector (DB25), just like a parallel printer port.
But the monitor connector carried a low voltage DC power supply
for the proprietary monochome monitor (12V or maybe 24V). This
power supply would blow up any printer that was accidentally
plugged in to the video socket.
I saw this happen in about 1987 on an Olivetti M24 that was
fitted with the EGC (Enhanced Graphics Controller), leaving
the original 25-pin monitor socket empty. Someone plugged
a parallel printer (a Hermes colour dot-matrix) into the
monitor socket, and it didn't work any more.
--
John Honniball
coredump at gifford.co.uk
The 6300 (and 6300 Plus) were designed and built
by Olivetti..
Their DB-25 video connector is the only reliable way ever
discovered to break a Radio Shack Daisy Wheel Printer II
I don't understand the line about the db25 monitor connector being able
to break a printer. Could you explain? 
6:27 p.m.
I don't understand the line about the db25 monitor
connector being able
to break a printer. Could you explain?
The Olivetti M24 (and I guess the AT&T 6300) used a DB25 conenctor for
the monitor -- socket on the back of the machine, plug on the monitor
cable. This connector carried power lines (+/-12V I think, maybe just +12V)
for a monochrome monitor.
If you plugged a normal PC printer cable into that socket, that supply
did nasty things ot the input logic (at least) of the printer on the
other end of the cable.
-tony
6279
days inactive
6281
days old
5 comments
5 participants
participants (5)
-
ard＠p850ug1.demon.co.uk -
coredump＠gifford.co.uk -
mloewen＠cpumagic.scol.pa.us -
trixter＠oldskool.org -
wdg3rd＠comcast.net