Before I take a few things apart to use for spare chips, power
supplies, screws, nuts, wires, etc., I'll ask: are there any
collectors of NCR minicomputer/multiprocessor equipment on this list?
If so, I'll go grab some part numbers.
One box, about three feet long, about a foot and a half wide, and about
three inches high, is some sort of SMD controller (sorry, I'm keeping
the 9" CDC hard drive, unless someone wants to swap reasonably
equivalent drives in case this may have some useful OS software,
etc. on it).
The other box appears to be a processor that was part of some
multi-processor system. Again, similar dimensions, except for it
being about 7 inches thick.
Price negotiable. Local pick-up only, but I may reconsider if someone
has something interesting to trade. :-) Don't wait too long, a blue
flame is waiting to be applied to the back of the circuit boards so
that I can retrieve some useful chips, re-use the power supplies (or
components thereof) and use the cases for other projects.
--
Copyright (C) 2003 R. D. Davis The difference between humans & other animals:
All Rights Reserved an unnatural belief that we're above Nature &
rdd(a)rddavis.org 410-744-4900 her other creatures, using dogma to justify such
http://www.rddavis.org beliefs and to justify much human cruelty.
Joe,
I'm in the U.S., and brought your (HP) tape drive... pse
contact me offlist with your shipping address so I can
drop it off..
Cheers,
Fred
--
Fred N. van Kempen, DEC (Digital Equipment Corporation) Collector/Archivist
Visit the VAXlab Project at http://VAXlab.pdp11.nl/
Visit the Archives at http://www.pdp11.nl/
Email: waltje(a)pdp11.nl BUSSUM, THE NETHERLANDS / Mountain View, CA, USA
On Dec 26, 14:35, Nico de Jong wrote:
> I've had a look at the floppy formats supported by my conversion
system,
> which btw originates in the UK. I havnt come across BBC formats in
the
> servicebureay, but according to the software BBC is found in quite
some
> flavours, reaching from single-side single-density 5.25" to DSDD 3.5"
> Before you spend a lot of time playing around with things, it would
be good
> to know the discs physicals and logicals.
The single-density "DFS" format is particularly easy. It consists of
10 sectors of 256 bytes per track, numbered 0 to 9, and is nominally
single-sided. If you have doubled-sided drives, side 0 of the first
drive is referred to as drive 0, and the sector headers are just as
you'd expect; the second side (side 1) is referred to as drive 2, and
has the *same* sector headers (ie the "head" number is stored in the
header as "0", not "1"). Drives can be either 40-track or 80-track;
the only difference (apart from the number of tracks, obviously) is the
size stored in the directory. Recording method is standard FM with an
Index Mark. There's no sector-to-sector interleave on a track, but the
start of each track is skewed by three sectors, compared to the
previous one.
The directory occupies the first two sectors of track 0, and is
extremely simple. I can describe it if you like, or give you a 512-byte
dump of the two sectors.
The double-density "ADFS" format is a bit more complicated. There are
several variations, but the BBC Micro (as opposed to the later
Archimedes) supported "S" (small) format (40 track SS), "M" (medium)
(40 track DS or 80 track SS), and "L" (80 track DS). The DS versions
are a little unusual in that they use all of side 0 before using any of
side 1, but the head numbers are what you'd expect (ie "0" for side 0
and "1" for side 1). Each track is 16 sectors of 256 bytes, numbered
0-15, no interleave, track-to-track skew of 9 (ie track one begins with
sector 9, track 1 begins with 2, track 2 with 11, etc), standard MFM
but normally *without* an Index Mark (though it shouldn't matter if you
put one in).
The directory's a bit more complicated becasue there's a proper free
space map, and it's a hierarchical structure.
--
Pete Peter Turnbull
Network Manager
University of York
Hi,
I was cleaning my office as I prepare to retire, and found several DECtapes
with programs I wrote for a PDP-9 in the mid 70's. I have no listings
available, but would like to read these programs if possible. I did a
Google search for DECtape, and came up with a posting you did Sep 4, 2002 on
getting a DECtape running. I was wondering if you have any pointers on
where I might get these tapes read? They would be written for 18-bit pdp-9,
but if I could get the images in any way I think I might be able to figure
out how to combine the blocks and translate the bit patterns to ascii.
Thanks in advance for any pointers. I have lost contact long ago with my
pdp9's and pdp11's.
Roy Thern
Roy Thern 631-344-7531 thern(a)bnl.gov RadCon Division, Bldg 120
In the data sheet, under the section "1. Non-IBM Formats" it says:
"Note that the Index Mark is not required by the 179X."
What does this mean exactly? How can a track contain any useful
imformation without a Index Mark?
Here is the whole paragraph for reference:
Variations in the IBM format are possible to a limited extent if the
following requirements are met: sector size must be a choice of 128,
256, 512, or 1024 bytes; gap sizes must be according to the following
table. Note that the Index Mark is not required by the 179X. The minimum
gap sizes shown are that which is required by the 179X, with PLL lock-up
time, motor speed variation, etc., adding additional bytes.
--
tim lindner
tlindner(a)ix.netcom.com
Hi everyone,
I'm interested in getting hold of a network ready MVII to host with the ISP
I work for. Curiosity value, but we can set up accounts on the machine for
other list members to use. Can anyone help?
Cheers
Stu B
Just wanted to share this with you - Santa dropped off a very cool
version of the Motorola 6800 MEK6800D2 trainer yesterday. The system was
installed in a custom-fitted case for use in a System Design course
taught at the University of Waterloo (Ontario,Canada), home of WATFOR
and WATFIV. There is a remote LED display relocated to the "dashboard"
area above the keyboard and a power supply is built in. Cassette and
expansion interfaces are brought out very neatly to the rear panel.
I don't know when this system was encased, but it could have actually
predated the SOL-20! I have no idea if the Hamilton Enclosure people
knew of Processor Tech or vice versa - maybe it was just a common
interest in Danish Modern design? Anyone have any more info?
Take a look - www.sideslip.net/vintage_computing/mek6800d2
Jack Rubin
Wilmette, Illinois
USA
I thought there might be a few folks on the list who might be interested
in these. I spoke with the owner of the manuals back in early October
after he sold the system these went with, and the buyer didn't want the
manuals. I convinced him not to throw them away, but we never worked out
shipping arrangements when I told him I was somewhat interested in them.
This should be a fairly complete set, but email the seller if you have any
questions.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4619&item=3647566680
He may also still have a BA350 available.
-Toth
Merry Christmas to all!
Obligatory pre-feast Christmas posting...
Hopefully there's some UK telecoms people on the list who can tell me
some more about these. I unearthed a pair of BT modems (look to be from
the mid 1980s), badged as Datel 4961x's.
They're in nice finned metal cases (with plastic end caps; Datel unicase
4001X's) - I think I hung onto them intending on using the shells to
house a pair of amplifiers, having never had any luck getting the modems
to work.
I was about to scrap them, and opened them up to strip and useful parts
first. Now I'm curious.
There's a *lot* of silicon inside these things. Most of the larger chips
appear to be custom, badged in a range from MS2006 to MS2011. One of the
40 pin chips carries the marking "BTRL / 403 / 5113". British Telecom
Research Labs maybe? There are three OKI 40 pin chips too, several ROMs,
and no less than 42 DIP switches internally.
There are six fuses inside - they didn't hold back there.
The rear of the case has a 25 pin DTE socket, a telephone pass-through
socket, PSTN socket for connection to the network - and also a
mysterious "PC" socket (same type as used for the phone network
connection). Any idea what that's for? ("Private Circuit" maybe)
The front has push-switches for 4800 baud operation, plus AL, ST, RDL
and DL. I assume ST is self-test, but I don't know what the others are.
There are status LEDs for 4800 operation, DSR, RFS, TD, CD, RD and test.
Those all make sense.
I remember I never got one of these to talk to a remote modem of any
type. I'm wondering if they're supposed to be used in pairs (or talk to
some specific remote equipment that I don't have) and use some sort of
non-standard data compression, or even encryption.
Any ideas anyone? Anybody know of any UK telecoms lists where there may
be people who can help?
cheers
Jules
