From: "Nelson H. F. Beebe" <beebe@math.utah.edu>
To: tuhs@minnie.tuhs.org
Subject: Re: [TUHS] core
Date: Thu, 21 Jun 2018 11:07:54 -0600 [thread overview]
Message-ID: <CMM.0.96.0.1529600874.beebe@gamma.math.utah.edu> (raw)
Tim Bradshaw <tfb@tfeb.org> commented on a paper by Tommy Flowers on
the design of the Colossus: here is the reference:
Thomas H. Flowers, The Design of Colossus, Annals of the
History of Computing 5(3) 239--253 July/August 1983
https://doi.org/10.1109/MAHC.1983.10079
Notice that it appeared in the Annnals..., not the successor journal
IEEE Annals....
There is a one-column obituary of Tommy Flowers at
http://doi.ieeecomputersociety.org/10.1109/MC.1998.10137
Last night, I finished reading this recent book:
Thomas Haigh and Mark (Peter Mark) Priestley and Crispin Rope
ENIAC in action: making and remaking the modern computer
MIT Press 2016
ISBN 0-262-03398-4
https://doi.org/10.7551/mitpress/9780262033985.001.0001
It has extensive commentary about the ENIAC at the Moore School of
Engineering at the University of Pennsylvania in Philadelphia, PA. Its
construction began in 1943, with a major instruction set redesign in
1948, and was shutdown permanently on 2 October 1955 at 23:45.
The book notes that poor reliability of vacuum tubes and thousands of
soldered connections was a huge problem, and in the early years, only
about 1 hour out of 24 was devoted to useful runs; the rest of the
time was used for debuggin, problem setup (which required wiring
plugboards), testing, and troubleshooting. Even so, runs generally
had to be repeated to verify that the same answers could be obtained:
often, they differed.
The book also reports that reliability was helped by never turning off
power: tubes were more susceptible to failure when power was restored.
The book reports that reliability of the ENIAC improved significantly
when on 28 April 1948, Nick Metropolis (co-inventor of the famous
Monte Carlo method) had the clock rate reduced from 100kHz to 60kHz.
It was only several years later that, with vacuum tube manufacturing
improvements, the clock rate was eventually moved back to 100Khz.
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next reply other threads:[~2018-06-21 17:20 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-21 17:07 Nelson H. F. Beebe [this message]
-- strict thread matches above, loose matches on Subject: below --
2018-06-21 22:44 Nelson H. F. Beebe
2018-06-21 23:07 ` Grant Taylor via TUHS
2018-06-21 23:38 ` Toby Thain
2018-06-21 17:40 Noel Chiappa
2018-06-21 13:46 Doug McIlroy
2018-06-21 16:13 ` Tim Bradshaw
2018-06-20 20:11 Doug McIlroy
2018-06-20 23:53 ` Tim Bradshaw
2018-06-19 12:23 Noel Chiappa
2018-06-19 12:58 ` Clem Cole
2018-06-19 13:53 ` John P. Linderman
2018-06-21 14:09 ` Paul Winalski
2018-06-19 11:50 Doug McIlroy
[not found] <20180618121738.98BD118C087@mercury.lcs.mit.edu>
2018-06-18 21:13 ` Johnny Billquist
2018-06-18 17:56 Noel Chiappa
2018-06-18 18:51 ` Clem Cole
2018-06-18 14:51 Noel Chiappa
2018-06-18 14:58 ` Warner Losh
[not found] <mailman.1.1529287201.13697.tuhs@minnie.tuhs.org>
2018-06-18 5:58 ` Johnny Billquist
2018-06-18 12:39 ` Ronald Natalie
2018-06-17 21:18 Noel Chiappa
2018-06-17 17:58 Noel Chiappa
2018-06-18 9:16 ` Tim Bradshaw
2018-06-18 15:33 ` Tim Bradshaw
2018-06-17 14:36 Noel Chiappa
2018-06-17 15:58 ` Derek Fawcus
2018-06-16 22:57 Noel Chiappa
[not found] <mailman.1.1529175600.3826.tuhs@minnie.tuhs.org>
2018-06-16 22:14 ` Johnny Billquist
2018-06-16 22:38 ` Arthur Krewat
2018-06-17 0:15 ` Clem cole
2018-06-17 1:50 ` Johnny Billquist
2018-06-17 10:33 ` Ronald Natalie
2018-06-20 16:55 ` Paul Winalski
2018-06-20 21:35 ` Johnny Billquist
2018-06-20 22:24 ` Paul Winalski
2018-06-16 13:49 Noel Chiappa
2018-06-16 14:10 ` Clem Cole
2018-06-16 14:34 ` Lawrence Stewart
2018-06-16 15:28 ` Larry McVoy
2018-06-16 14:10 ` Steve Nickolas
2018-06-16 14:13 ` William Pechter
2018-06-16 13:37 Noel Chiappa
2018-06-16 18:59 ` Clem Cole
2018-06-17 12:15 ` Derek Fawcus
2018-06-17 17:33 ` Theodore Y. Ts'o
2018-06-17 19:50 ` Jon Forrest
2018-06-18 14:56 ` Clem Cole
2018-06-18 12:36 ` Tony Finch
2018-06-16 12:58 Doug McIlroy
2018-06-20 11:10 ` Dave Horsfall
2018-06-16 12:51 Noel Chiappa
2018-06-16 13:11 ` Clem cole
2018-06-15 15:25 Noel Chiappa
2018-06-15 23:05 ` Dave Horsfall
2018-06-15 23:22 ` Lyndon Nerenberg
2018-06-16 6:36 ` Dave Horsfall
2018-06-16 19:07 ` Clem Cole
2018-06-18 9:25 ` Tim Bradshaw
2018-06-19 20:45 ` Peter Jeremy
2018-06-19 22:55 ` David Arnold
2018-06-20 5:04 ` Peter Jeremy
2018-06-20 5:41 ` Warner Losh
2018-06-15 11:19 A. P. Garcia
2018-06-15 13:50 ` Steffen Nurpmeso
2018-06-15 14:21 ` Clem Cole
2018-06-15 15:11 ` John P. Linderman
2018-06-15 15:21 ` Larry McVoy
2018-06-16 1:08 ` Greg 'groggy' Lehey
2018-06-16 2:00 ` Nemo Nusquam
2018-06-16 2:17 ` John P. Linderman
2018-06-16 3:06 ` Clem cole
2018-06-20 10:06 ` Dave Horsfall
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