From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
To: tuhs@minnie.tuhs.org
Cc: jnc@mercury.lcs.mit.edu
Subject: Re: [TUHS] core
Date: Sat, 16 Jun 2018 18:57:41 -0400 (EDT) [thread overview]
Message-ID: <20180616225741.F121718C0A7@mercury.lcs.mit.edu> (raw)
> From: Johnny Billquist
> incidentally have 18 data bits, but that is mostly ignored by all
> systems. I believe the KS-10 made use of that, though. And maybe the
> PDP-15.
The 18-bit data thing is a total kludge; they recycled the two bus parity
lines as data lines.
The first device that I know of that used it is the RK11-E:
http://gunkies.org/wiki/RK11_disk_controller#RK11-E
which is the same cards as the RK11-D, with a jumper set for 18-bit operation,
and a different clock crystal. The other UNIBUS interface that could do this
was the RH11 MASSBUS controller. Both were originally done for the PDP-15;
they were used with the UC15 Unichannel.
The KS10:
http://gunkies.org/wiki/KS10
wound up using the 18-bit RH11 hack, but that was many years later.
Noel
next reply other threads:[~2018-06-16 22:57 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-16 22:57 Noel Chiappa [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 17:07 Nelson H. F. Beebe
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
[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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