On 09/10/2015 11:11 PM, Gary Oliver wrote:
FWIW I noticed this started several weeks ago - been
trying to get to look at current crop of home builts and
could not find a way to the web ring.
Here's the latest list out of the javascript file that one
of the ring members in Germany got me a cop
ecessarily. It may be possible that filtering
software/hardware statistically let a few accesses get
through. This may be intentional or just due to overloaded
nodes. But, YES, it IS very interesting, as so MANY others
who could not access the members.iinet page were finding
they got stopped at cogentco.
Jon
countries had no problem
(Sweden, Ireland, UK).
Thanks again for taking the time to help research!
Jon
being able to get to all the other pages
of the ring.
And, with the great help of the classiccmp group, we have
scoped out that this is actually a pretty large problem,
about 54% of US and Canadian users cannot get to anything on
members.iinet.net.au
Jon
tainly
would get more brittle as they aged.
But, yes, it was a fairly simple machine, I don't think you
could strip a tube computer down much further than the G-15
and still have it do useful work.
Jon
on it and see all the intricate wiring, tubes and
construction.
One of the Texas Microsystems founders (and a Rice alum) got possession, and
after a few years gave it back to Rice.
Any pictures of this?
Jon
les in the drive seek electronics
that only occur on longer seeks.
Jon
hat this was a widespread blockage.
Thanks!!!
Jon
ively track how long
the horizon on the login failures is set, and they've been
programmed to give up on any node that has a horizon over 2
weeks.
Jon
eck.
So MANY other weaknesses could easily be caused by
accident. Like, the file that contained valid account
numbers was often not protected. Anybody could just print
out that file.
Jon
t to be
NOT writeable by the program. This avoids a LOT of simple
mistakes and REALLY hard to find program crashes.
This is true of MS, Linux/Unix and the VMS program
environment that I have used for about 40 years. I think
you have to go back to maybe Windows 95 or RT-11 to not have
that protection.
Jon
On 09/17/2015 12:49 AM, Dave G4UGM wrote:
in my
humble opinion many Linux users are rather more blasé
about the
security of the OS that they should be
Absolutely true, and I will admit that I have fallen into
the trap, too. But, it has worked well so far!
Jon
the later X86 machines have a tiny block of patch
microcode that is available to the OS to put special
routines into.
Jon
On 09/17/2015 11:19 PM, Guy Sotomayor wrote:
On 9/17/15 8:55 PM, Jon Elson wrote:
I think the later X86 machines have a tiny block of patch
microcode that is available to the OS to put special
routines into.
Certainly not Intel CPUs. All of the microcode patches
are loaded via special
That caused a line to print
during the boot. The typical dot matrix printer console on
the 780 was also connected to/through the LSI-11.
Jon
I do remember a big upgrade (glad we had DEC service!) that
involved upgrading/installing WCS for
some version of VMS to run. So, after a certain vintage of
VMS (at least) you HAD to have WCS on the 780.
Jon
.
Most likely you'd have odd crashes or something.
Jon
see if
there might be.
Jon
nterface
used at the
time. Even that gave a very small amount memory per track.
It was fairly easy to make CP/M work with other disk types
and formats. Even **I** was able to write a driver to add a
SASI Winchester drive to my CP/M system. (That made it run
SOOO much better!)
Jon
d with the host
computer and plotter main board by serial. Both boards had
68K processors.
Jon
rs in implementing the standard
FORTRAN language, and also printing out floating point
numbers was laughably slow. We decided to go with RSX-11M
instead. That experience put me off Unix-derived systems
for years. it made me think that that version of FORTRAN
was not likely to have ever been used very much.
Jon
PDP-7.
So, B was never actually a FORTRAN compiler, just Ken
started thinking about FORTRAN grammar and within one DAY
took off in a different direction. By that time (1969 or
so) FORTRAN was a really old language, and considered way
out of date by most universities' Comp Sci departments.
Jon
compliant implementation, you'd just
about have to generate some kind of code interpreted by an
interpreter that ran on the 1401 directly.
Jon
On 09/22/2015 08:49 PM, Chuck Guzis wrote:
On 09/22/2015 06:31 PM, Jon Elson wrote:
So, B was never actually a FORTRAN compiler, just Ken
started
thinking about FORTRAN grammar and within one DAY took
off in a
different direction. By that time (1969 or so) FORTRAN
was a really
old language
ht check outfits like MSC that sells
a lot of machine tool supplies. Also Carr-Lane has them,
under "leveling feet".
Jon
construction, but
many of them follow the above general design.
Jon
old DEC fans, from PDP-8 and
PDP-11 models, are totally standard size, and can still be
bought new from Digi-Key, Mouser, etc. If it is more than a
few drops of oil needed, then it makes NO SENSE to repair
windings on a fan you can get for $15.
Jon
es, maybe the best fans do run over $15.
Jon
ramic cap,
0.1 uF value. It is definitely non-polarized.
I did see these at one time, I think they were to make the
ceramic caps more durable. They are basically the same as
an SMT multilayer ceramic that would be used today, but in
an axial lead format.
Jon
St. Louis, MO, USA.
Jon
pport enough memory to
properly run.
Jon
On 10/04/2015 12:18 AM, Zane Healy wrote:
On Oct 3, 2015, at 5:21 PM, Jon Elson wrote:
No, absolutely not. I know that 4.3-4.7 will not run (properly) on a KA-650.
In general, it boots up, but doesn't have a machine check handler that is
compatible with the 650 architecture. I ran
On 10/04/2015 08:30 AM, Glen Slick wrote:
On Sat, Oct 3, 2015 at 10:18 PM, Zane Healy wrote:
On Oct 3, 2015, at 5:21 PM, Jon Elson wrote:
No, absolutely not. I know that 4.3-4.7 will not run (properly) on a KA-650.
In general, it boots up, but doesn't have a machine check handler th
ve to check the manual to see how the Unibus is wired.)
Jon
.)
I ran it until 2007, although I moved all new software
development to other systems after the mid 90's.
Jon
nd on.
This is probably only of interest if you are flying in/out
through Houston, however.
Jon
en one of these up, make sure to oil the cotton
packing to supply oil gradually to the bearing.
Jon
own that if you put a
complete fill of ATF into an engine crankcase, the rings
will last about 10 miles before the compression goes to zero.
If you put engine oil in the transmission, then the clutches
will slip.
Jon
ut, it was too cumbersome for
our physicists to go through all that hassle, and we had no
debugging facility in that attached processor mode. (I
could have hacked some kind of error message queue to the
system.)
Jon
Jon
both Genix and then Xenix on the
Logical Microcomputer Co. 32016 we bought.
Jon
ation of the
Z-80 you are using. I built some battery-powered stuff
using a Harris Z-80 clone that was all CMOS. Some timings
were a bit different from a Zilog Z-80.
Jon
of it.
Jon
put
heat sinks on them, they ran that hot. Obviously, large
main memory was going to have to run slower.
Jon
On 04/22/2016 11:10 PM, Jon Elson wrote:
Yikes, too many typos, let me try over!
I built a 32-bit micro-engine for a project that was
eventually going to be an IBM 360-like CPU.
I picked the 360, not because it was the greatest design,
but it was VERY well laid-out and would be easy to write
te a few machines. Among the PDP-11's alone, it is
found in the -11/45, /05, /40, /04 and /34, to name a few that I checked
quickly, and almost certainly others too (e.g. /70).
The 11/45 and 11/70 are mostly the same processor.
Definitely, the data paths boards and FPU are the same part
numbers.
Jon
On 04/23/2016 11:29 AM, Noel Chiappa wrote:
> From: Jon Elson
> The 11/45 and 11/70 are mostly the same processor. ...
> the data paths boards and FPU are the same part numbers
'Yes' to the FPP (well, there are two versions, the FP11-B and FP11-C, but
they ar
may have been worried about availability, or
possibly the part going obsolete.
Those are other issues that a designer might be concerned
about, as well as reliability.
Jon
families had very short lifetimes before their makers hopped
onto the next new thing. (Oh, yeah, you said the same thing
in the last sentence!)
Jon
had tons of boards out of computers and electronic
equipment. The best stuff was kept in front in glass cases
next to the cash register.
Jon
ms from (Ughhh!)
Borland Turbo Pascal for Windows to Linux, and it was a
surprisingly painless job. The only thing I notice is the
error messages look exactly like Borland error messages on
DOS. (Error 132 at 1B7F sort of thing.)
Jon
On 04/25/2016 12:30 PM, Chuck Guzis wrote:
On 04/25/2016 09:39 AM, Jon Elson wrote:
I used it to port a couple of my programs from (Ughhh!) Borland
Turbo Pascal for Windows to Linux, and it was a surprisingly painless
job. The only thing I notice is the error messages look exactly like
Borland
On 04/25/2016 12:42 PM, geneb wrote:
On Mon, 25 Apr 2016, Chuck Guzis wrote:
On 04/25/2016 09:39 AM, Jon Elson wrote:
I used it to port a couple of my programs from (Ughhh!)
Borland
Turbo Pascal for Windows to Linux, and it was a
surprisingly painless
job. The only thing I notice is the
rtial
measuring unit and moving it around, there's 3 racks of gear
to support it.
Jon
On 04/26/2016 12:14 PM, Swift Griggs wrote:
On Tue, 26 Apr 2016, Jon Elson wrote:
Erik is not the only one. Check out Tatiana van Vark.
Excellent! I've actually wondered who in the world might do something like
this. Now I know. Like I said, what a cool hobby.
Here's a picture
floating-point
multiplier and adder, some address arithmetic logic and a
sequencer.
Jon
On 04/26/2016 09:47 PM, William Donzelli wrote:
What was the highest level of integration in a single envelope?
Perhaps Selectrons.
There were also "Compactrons", 12-pin tubes kind of
extending the 7- and 9-pin submini tubes.
Some of them had at least 3 elements in one envelope.
Jon
the technology of the time.
Jon
On 04/27/2016 09:34 PM, Eric Smith wrote:
On Wed, Apr 27, 2016 at 7:09 PM, Jon Elson wrote:
Sure. A VAX 11/780 had a 5 MHz clock! Would be hard for an emulator to NOT
beat that! Later models did run faster, but not vastly faster, due to the
technology of the time.
I'm not sure what
t
defines the characters.
Jon
On 04/28/2016 10:46 AM, Rod Smallwood wrote:
On 28/04/2016 16:32, Jon Elson wrote:
Have you tried MetaFont? I've never actually created a
font with it, just used it automatically within the TeX
environment. But, there is a human-readable language
that defines the characters.
J
ivative of Metafont.
Google pulls up a vast number of articles on metafont to
vector, for instance.
Jon
oblem if just reading or writing a page of text, but if
handling hundreds of K you definitely notice. Binary I/O
seemed to be OK.
Jon
X came out.
Jon
regardless of how many bulbs I want to drive? You say
"within limits". What specification do I look for to
understand the limits? Thanks
LED lighting power supplies are generally rated in mA
output, within a range of voltages, such as
350 mA within 24:72 V DC.
Digi-Key stocks something like 10,000 models!
Jon
n it. It was the size of a
refrigerator.
And another, the LINC, discrete transistor machine, 2K
12-bit words and a software driven screen, so it was
actually interactive. Storage was LINCtapes, the predecessor
to DECtapes. Fit in a single 5' relay rack, with a console
on a desk.
Jon
ystems use a variant of ECL,
which of course really burned power, too.
Jon
/fb_comphist/418-II.jpg
The printer frame in the back looks VERY much like a
Teletype model 19. The keyboard in front is reminiscent of
a model 15/19 keyboard, but has 4 rows, so it can't be from
a 5-bit teletype.
Jon
36-input diode gates with
pull-up resistors. You have two choices of resistor,
low-power and fast.)
The Xilinx CoolRunner II is quite low power, basically a
CMOS FPGA architecture.
Jon
On 05/07/2016 02:05 PM, Jon Elson wrote:
On 05/07/2016 12:35 PM, Chuck Guzis wrote:
On 05/06/2016 10:26 AM, Paul Koning wrote:
I think a well chosen hearing aid tube can outperform a
classic (not
L or LS) 7400 series IC.
This application sound like a perfect candidate for a CPLD.
The
On 05/07/2016 03:46 PM, Chuck Guzis wrote:
On 05/07/2016 12:05 PM, Jon Elson wrote:
The Xilinx 9500 series of CPLDs are not low-power, by any means.
They have a formula in the data sheet and a power calculator program,
that are both WRONG! They underestimate power by a factor of 3!! I
ar on eBay. Some of
it goes fairly cheap, the older it is the cheaper.
You can likely find the right acq modules within a month.
The 91xx is REALLY old, too, so should cost more to ship the
modules than the price for the units themselves.
Jon
non-polar capacitor in
the vertical sweep circuit. That is a real common flaw in
old TVs and video monitors.
Jon
t one
arc second. That was my weight deflecting the concrete
floor of my basement, causing the lathe to tilt slightly.
All structures, including the earth, deflect under load.
Jon
pply, but this was just a capacitor on a board. I've
never had a Corcom or other brand of power entry/line filter
go bad.
So, I think that one particular type might have had some
kind of manufacturing defect.
Jon
On 05/13/2016 01:30 PM, Dave Wade wrote:
What has this got to do with Classic Computers
Well, I still have the backup tape from my CP/M system.
(Yes, I had a 9-track, 800 BPI Pertec tape drive on my CP/M
system.)
Jon
o, you
had to check for that special case.
Jon
had a few switches that were
multi-position, Such as stop/single-step and load
address/examine, otherwise they were all on-off.
IBM 360's had a row of switches that were multi-position,
mostly for FE diagnostic purposes. The data and address
switches were all on/off.
Jon
On 05/24/2016 11:32 AM, Swift Griggs wrote:
On Tue, 24 May 2016, Jon Elson wrote:
The PDP-5 I did a fair bit of work on needed a bootstrap program loaded
in from switches, it had no internal ROM for that.
How long did it usually take to do it?
We had contests, I think some people got under 15
first microcomputers had blinkenlight front
panels, and they were pretty much gone from minis and mainframes by the
late-70s.
The early PDP-11s had a diode matrix ROM for the boot
memory. You could change the boot code with a wire cutter
and soldering iron.
Jon
That's actually just the DSKY (display keyboard), the
computer was about the size of 2 shoeboxes. The DSKY was
actually quite small, about 5 x 6", I think.
Jon
On 05/24/2016 11:56 AM, Swift Griggs wrote:
On Tue, 24 May 2016, Jon Elson wrote:
The early PDP-11s had a diode matrix ROM for the boot memory. You could
change the boot code with a wire cutter and soldering iron.
Is that similar to "wire wrap" ? I remember my grandmother talking ab
lower 16
switches. The data switches were readable as one I/O
register. When you read it, it reported the switches. When
you wrote to it, some models could display it on the panel.
These were used in some diagnostic programs.
Jon
27;t remember the name of this system. A big piece
of gear, two or 3 relay racks full of boards, was built
using this at a VERY prior place of employment, so that was
in 1969.
Jon
ntrol store. The control
store was just the top 16 KB of main core memory! To change
emulators, restore from a microprogram crash, etc. you
loaded the emulator from a card deck!
Jon
rough the wires leaves the end bare copper, so
the plating process connects to all wires that pass across
where the hole is drilled. It is quite amazing that it
works at all! The one downside is that rework of the
boards, as in replacing chips, is a VERY delicate operation.
Jon
ame for it.
Note the posts are not square - they're not standard wire-wrap posts with a
different connector.
YUP!!! THAT'S IT! Even the wires are yellow, as I remember
them! The system was made by AMP.
Jon
s
from the 1's bit line pad, you got a 1 in the control store
bit. if the non-driven line was wide across from the 1's
bit line pad, you got a zero.
The mylar sheet was not punched, so changing the microcode
required replacing a whole bunch of etched circuit boards.
Jon
On 05/24/2016 09:29 PM, Chuck Guzis wrote:
On 05/24/2016 07:05 PM, Jon Elson wrote:
And the 360/25 had all writeable control store. The control store
was just the top 16 KB of main core memory! To change emulators,
restore from a microprogram crash, etc. you loaded the emulator from
a card
On 05/24/2016 11:47 PM, Chuck Guzis wrote:
On 05/24/2016 08:48 PM, Jon Elson wrote:
For sure! The 360/30 was an 8 BIT machine, 8-bit memory, 8-bit data
paths, etc. Really hobbled the performance, and restricted the
peripherals that could be attached. The models /22 and /25 had 16-bit
memory
On 05/25/2016 12:01 PM, Noel Chiappa wrote:
> From: Jon Elson
> the /20 was intended for very specific uses in 360 shops, and maybe as
> an entry-level "foot in the door" to move totally tab card shops into
> the 360 family. The only /20s I ever sa
On 05/25/2016 12:11 PM, Chuck Guzis wrote:
On 05/25/2016 10:06 AM, Jon Elson wrote:
The only language supported on the 360/20 was RPG. For a mostly tab
card type of operation, you could actually do a lot in RPG.
Otherwise, you had to write in machine language and get it assembled
on another
lowest possible level.
I can easily imagine the 729 series of drives may have had a
very similar interface. So, it may be possible that these
could be interchanged fairly easily.
Jon
On 05/25/2016 05:31 PM, Noel Chiappa wrote:
> From: Jon Elson
>> I interned at IBM Bermuda, and they had a 360/20 as their main service
>> bureau machine; it had (IIRC) ... a 4301 printer.
> I'm guessing, maybe, that would be a 1403 printer?
Ah, righ
photo I've seen of a
/30 ROS card!
Jon
s and all zeros and read back and check
parity.
This was a quick check that major components of the machine
were in operating order. (I don't recall if you needed the
CE key to do these tests.)
Jon
e look was pretty iconic. The printed output was
then photographed to make offset printing plates. (Later
they used IBM composer word processing printers, and they
looked nicer, with proportional spacing.)
Jon
On 05/26/2016 12:33 PM, Brent Hilpert wrote:
On 2016-May-25, at 6:14 PM, Jon Elson wrote:
On 05/25/2016 05:31 PM, Noel Chiappa wrote:
> From: Jon Elson
>> I interned at IBM Bermuda, and they had a 360/20 as their main service
>> bureau machine; it had (IIRC) ...
B2 bomber gets the mission data loaded on a Maxxoptix
optical cartridge. I recognized it as I have a Maxxoptix
drive here. Not quite as old as 7-track mag tape, but a
fairly old technology. it was probably state of the art
when the were first designing the B2.
Jon
g about this in relation to keeping a mid-size
360 running for a few hours a month at a museum, like the
1401 at CHM. But, it would sure work for actual full-time
operation, too.
Jon
e
their toll at a slower rate. Remember, all this gear is now
about 50 years old!
Jon
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