Discussion:
Blinky lights WAS: The SR-71 Blackbird was designed ENTIRELY with slide rules. (fwd)
(too old to reply)
Lee Ayrton
2005-05-20 16:03:06 UTC
Permalink
Compare: a mechanical integrator might be a rotating table driving a
wheel on a splinted shaft with the output being the revolutions of the
shaft. An electronic integrator is an op amp and a capacitor. What's the fun in
watching that?
Dials [big freaking ones, not wimpy little meters], plotters, meters,
etc. all whizzing around like a cheap SF movie on meth. None of those
sissified blitta blitta lights either. And every now and then, a big
puff of magical smoke and even faster whizzing.


This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?



Lee "Inquiring mind" Ayrton


* Yes, spinning tape decks also stood for "computer" but that's a
different question.
John Francis
2005-05-20 16:51:17 UTC
Permalink
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
The computers of that era had front panels that were mostly filled
with three different items:

1) Rows of little lights (individual lights are usually round, and
a quarter of an inch or so in diameter)

2) Rows of rocker switches

3) Lighted indicator switches (alone or in rows). These are closest
to what you describe above; they appear as little square panels
(around three quarters of an inch square). Each switch also had
a light bulb behind it (occasionally more than one).

(there would, quite frequently, also be several rotary switches)

For an example, see the front panel of the SAGE computer:

<URL:Loading Image...>

The rapidly-changing displays would generally be the little lights;
the indicator switches usually displayed the state of the switch.
'The more powerful the computer, the more blinky lights' does have
some degree of truth - here's the front panel of one of the more
powerful computers of that era, the IBM 360 Model 195:

<URL:Loading Image...>

The most powerful computers, though - the first supercomputers
such as the Control Data CDC 6600 or the early Cray machines -
had very simple control panels, with very few indicators.


The visual paradigm you describe (which I remember from several
TV shows such as 'The Avengers' as having lighted squares perhaps
two inches across) would be more likely to be found in a discotheque
(or on the bridge of the starship Enterprise) than in a computer room
Lee Ayrton
2005-05-20 22:19:37 UTC
Permalink
Post by John Francis
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
The computers of that era had front panels that were mostly filled
1) Rows of little lights (individual lights are usually round, and
a quarter of an inch or so in diameter)
2) Rows of rocker switches
3) Lighted indicator switches (alone or in rows). These are closest
to what you describe above; they appear as little square panels
(around three quarters of an inch square). Each switch also had
a light bulb behind it (occasionally more than one).
(there would, quite frequently, also be several rotary switches)
<URL:http://panix.com/~johnf/temp/chm-5.jpg>
The rapidly-changing displays would generally be the little lights;
the indicator switches usually displayed the state of the switch.
'The more powerful the computer, the more blinky lights' does have
some degree of truth - here's the front panel of one of the more
<URL:http://panix.com/~johnf/temp/chm-6.jpg>
The most powerful computers, though - the first supercomputers
such as the Control Data CDC 6600 or the early Cray machines -
had very simple control panels, with very few indicators.
The visual paradigm you describe (which I remember from several
TV shows such as 'The Avengers' as having lighted squares perhaps
two inches across) would be more likely to be found in a discotheque
(or on the bridge of the starship Enterprise) than in a computer room
(Long quote, couldn't find places to snip) Good stuff, thanks. When I
posted that question what I had in mind was the TV series _Voyage To The
Bottom Of The Sea_. Here's a glimpse of what I was wondering about:

<URL:http://www.vttbots.com/interiors_1.html>

Scroll down to the two B&W photos captioned "comtrol room".

From the URL this particular incarnation of the Blinky Light Computer
goes back to 1957 and was clearly intended to be over the top, but by
the early 1960s it looked like what a computer should to ordinary
humans. Anyone know of earlier movie examples?


Movie sets and props are all about how they look to the masses, nothing
else.
BobMac
2005-05-20 17:27:17 UTC
Permalink
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.

It could be true; IBM used to be that obsessed about customer happiness.

rm
Nick Spalding
2005-05-20 17:38:43 UTC
Permalink
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.
It could be true; IBM used to be that obsessed about customer happiness.
They were of little use when the machine was running but essential when one
was trouble-shooting and single-stepping the machine.
--
Nick Spalding
John Francis
2005-05-20 17:58:01 UTC
Permalink
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.
When DEC introduced the third version of the PDP-10/DECSystem-10, the
KL-10, it had practically no blinky lights on the outside (and only a
PDP-11/35 console display inside if you opened up the cabinet doors).

Somebody (MIT, I believe, although it could have been BB&N) cobbled up
a display using an empty CPU cabinet from an earlier model of PDP-10,
which still had all the light panels installed. THey even labelled it
with a semi-official looking DEC part number: KL-UDGE

I've heard it explained as (U)ser (Display) in (G)raphical (E)lements,
but I don't recall that explanation being current at the time.
(I actually saw the cabinet in question, hooked up to the KL-10)
Sarr J. Blumson
2005-05-20 18:23:43 UTC
Permalink
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.
Obviously not someone who ever had to debug sitting at the console and
pressing buttons to step through a program one instruction at a time and
watch what was happening by watching the lights.

Some of us have even had the experience of standing and staring at the
lights for a few minutes and diagnosing broken hardware.
--
--------
Sarr Blumson ***@alum.dartmouth.org
http://www-personal.umich.edu/~sarr/
Morten Reistad
2005-05-20 19:30:02 UTC
Permalink
Post by Sarr J. Blumson
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.
Obviously not someone who ever had to debug sitting at the console and
pressing buttons to step through a program one instruction at a time and
watch what was happening by watching the lights.
Some of us have even had the experience of standing and staring at the
lights for a few minutes and diagnosing broken hardware.
Well, I know the film industry has "computer blinkenlights" panels, to
make computers more "blinkingflashing".

At a PPOE I made a program that made the tapes spin and make
"old Hollywood mainframe movements", ditto with the lights on the
comms controllers. It was run for a number of photo/film sessions,
and the result is still in some broadcasting stock footage.

But, at the same PPOE the lights were really used. They had built
redundancy into everything; but in the mid-80s they didn't have
management for it all, so they had some near disasters because
the failover worked, but noone got a notice to replace the failed
part.

There was a twice daily routine to go check the cabinet lights. There
were several hundred things that were checked. They embraced SNMP
when it arrived.

-- mrr
Anne & Lynn Wheeler
2005-05-20 19:50:05 UTC
Permalink
Post by Morten Reistad
There was a twice daily routine to go check the cabinet lights. There
were several hundred things that were checked. They embraced SNMP
when it arrived.
from my view, snmp had some interesting wars in the 80s. at interop
88
http://www.garlic.com/~lynn/subnetwork.html#interop88

snmp was still duking it out with the other contenders

there was some amount of osi out in force also (the world govs. were
starting to mandate the internet be eliminated and everything be
converted to osi).

I got a couple workstations in a booth diagonal from a booth that case
had snmp being demo'ed (about 10-15' away) ... and case was convinced
to help with an after hours snmp port to the workstations (demo it on
other machines than his).

from my rfc index:
http://www.garlic.com/~lynn/rfcidx3.htm#1067

1067 -
Simple Network Management Protocol, Case J., Davin J., Fedor M.,
Schoffstall M., 1988/08/01 (33pp) (.txt=67742) (Obsoleted by 1098)
(See Also 1065, 1066) (Refs 768, 1028, 1052) (Ref'ed By 1089,
1095, 1156, 1704)

or
http://localhost/rfcauthor.htm#xaCaseJ

Case J. (***@snmp.com)
3412 3410 2572 2570 2272 2262 1908 1907 1906 1905 1904 1903 1902
1901 1628 1512 1452 1451 1450 1449 1448 1444 1443 1442 1441 1285
1157 1098 1089 1067 1028
--
Anne & Lynn Wheeler | http://www.garlic.com/~lynn/
Anne & Lynn Wheeler
2005-05-20 19:55:37 UTC
Permalink
oh yes, past posts mentionding sr-71
http://www.garlic.com/~lynn/2000f.html#13 Airspeed Semantics, was: not quite an sr-71, was: Re: jet in IBM ad?

... there are a different set of stories from boyd
http://www.garlic.com/~lynn/subboyd.html#boyd
http://www.garlic.com/~lynn/subboyd.html#boyd2

doing the F16.
--
Anne & Lynn Wheeler | http://www.garlic.com/~lynn/
Jack Peacock
2005-05-20 20:28:08 UTC
Permalink
Post by Sarr J. Blumson
Some of us have even had the experience of standing and staring at the
lights for a few minutes and diagnosing broken hardware.
The first clue is, while staring at the data bus, a bit slowly fades off and
back on...intermittent contact varying by board temperature. The easy ones
were depositing one bit on, but two lights come on...solder bridge. Or
deposit a one but it shows a zero...data line shorted to ground. Then there
was the case of many bits randomly changing...intermittent on an address
line, so data flipped between two locations at random. While a memoy test
would usually find these problems, the advantage of a front panel display is
being able to extend the problem board out of the card cage and logic probe
it to track down the errant solder joint or bad chip in situ.

Certain address/data patterns indicating a crash quickly become obvious too.
One good indication is a nicely decrementing address bus, as it marches
through memory destroying all in its path. This was a common occurrence on
8080/z80 systems since the FF opcode (typical data returned for non-existent
memory) was a RST 7 (CALL 38H), which rapidly walked the stack pointer down
from wherever it was set, then wrapped back to high memory and started over.
Many memory tests, and even a front panel, would not catch the infamous M1
memory timing gotcha on Z80 processors, where the first byte of an
instruction fetch required faster access than subsequent fetches. A symptom
of this was a missed instruction which then fell into a FF type loop.

A highly active front panel can be used as a measure of processor activity,
so the rapidly changing lights stereotype was probably derived from some
screenwriter's short tour of an old mainframe site. The earliest versions
of the blinkenlight syndrome I can recall are from some mid-50s movies, "Gog
and Magog" (a real IBM 650?) and "The Invisibile Boy" (fake panel of light
squares). "War of the Worlds" (Gene Barry version, 1953) featured a
mechanical difference analyzer instead of a computer, so it must have
started after that particular movie.
Jack Peacock
Sam Seiber
2005-05-20 22:02:27 UTC
Permalink
Post by Jack Peacock
Certain address/data patterns indicating a crash quickly become obvious too.
One good indication is a nicely decrementing address bus, as it marches
through memory destroying all in its path. This was a common occurrence on
8080/z80 systems since the FF opcode (typical data returned for non-existent
memory) was a RST 7 (CALL 38H), which rapidly walked the stack pointer down
from wherever it was set, then wrapped back to high memory and started over.
Many memory tests, and even a front panel, would not catch the infamous M1
memory timing gotcha on Z80 processors, where the first byte of an
instruction fetch required faster access than subsequent fetches. A symptom
of this was a missed instruction which then fell into a FF type loop.
A condition I referred as "stacking itself to death". When I saw that
on
my Altair 8800, I would quickly regret the fact I forgot to hit the
Memory Protect switch, to make my RAM in fact ROM. That was followed by
toggling in the program again.

Sam
Joe Pfeiffer
2005-05-20 19:54:18 UTC
Permalink
I have very fond memories of debugging tiny programs, entered using
toggle switches on the front panel, watching the blinkenlights telling
me what was going on, on a DCC-116 (Data General Nova clone) in the
mid 1970s.

Also, the campus had a Burroughs B(something or other) that had a
large panel of incandescent lights that could have been used for
debugging, but in fact just showed a big letter B.
--
Joseph J. Pfeiffer, Jr., Ph.D. Phone -- (505) 646-1605
Department of Computer Science FAX -- (505) 646-1002
New Mexico State University http://www.cs.nmsu.edu/~pfeiffer
a***@NOW.AT.arargh.com
2005-05-20 22:23:01 UTC
Permalink
Post by Joe Pfeiffer
I have very fond memories of debugging tiny programs, entered using
toggle switches on the front panel, watching the blinkenlights telling
me what was going on, on a DCC-116 (Data General Nova clone) in the
mid 1970s.
Been there, done that, still got the hardware. (4 of them) :-)
--
ArarghMail505 at [drop the 'http://www.' from ->] http://www.arargh.com
BCET Basic Compiler Page: http://www.arargh.com/basic/index.html

To reply by email, remove the garbage from the reply address.
John Ings
2005-05-20 21:22:31 UTC
Permalink
Post by Sarr J. Blumson
Obviously not someone who ever had to debug sitting at the console and
pressing buttons to step through a program one instruction at a time and
watch what was happening by watching the lights.
Some of us have even had the experience of standing and staring at the
lights for a few minutes and diagnosing broken hardware.
Indeed! You could tell when the program was trapped in an endless loop
because of a programmer goof, or when it had hit a STOP command, or if
it was patiently waiting at a port for input. When they became
obsolete I kinda missed those blinkenlights sometimes.

ACHTUNG! ALLES LOOKENSPEEPERS!

Alles touristen und non-technischen looken peepers!
Das computermachine ist nicht fuer gefingerpoken und mittengrabben.
Ist easy schnappen der springenwerk, blowenfusen und poppencorken
mit spitzensparken. Ist nicht fuer gewerken bei das dumpkopfen.
Das rubbernecken sichtseeren keepen das cotten-pickenen hans in das
pockets muss; relaxen und watchen das blinkenlichten.
Jack Peacock
2005-05-20 23:20:29 UTC
Permalink
Post by John Ings
Indeed! You could tell when the program was trapped in an endless loop
because of a programmer goof, or when it had hit a STOP command, or if
it was patiently waiting at a port for input.
On S-100 machines one way to debug interrupts, and monitor interrupt load,
was to set up the idle task as a HALT. If there was a problem in
programming the interrupt controller it would hang on HALT (faulty memory
says it was 66H on the data bus), no address/data line activity, but the
interrupt request was lit. Usually a sign of a service routine bug, or the
priority level on the interrupt controller was set too high to accept the
request.

If there were no bugs the relative brightness of the INT (interrupt request)
and HALT would give an idea of interrupt/processor load, along with PHLDA
(DMA ack) to show the disk controller activity. All it took to gauge the
health of an MP/M multi-tasking system was a quick look at the front panel.
Jack Peacock
m***@aol.com
2005-05-20 21:47:54 UTC
Permalink
Post by Sarr J. Blumson
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random
intervals.* The
Post by Sarr J. Blumson
Post by BobMac
Post by Lee Ayrton
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting
indication
Post by Sarr J. Blumson
Post by BobMac
that something was actually happening.
Obviously not someone who ever had to debug sitting at the console and
pressing buttons to step through a program one instruction at a time and
watch what was happening by watching the lights.
Some of us have even had the experience of standing and staring at the
lights for a few minutes and diagnosing broken hardware.
The General Automation SPC-16 mini had a pin on the blinken light panel
that produced a voltage proportional to which lamps were lit, a cheesy
D/A converter. I don't know what it was intended for, But I connected
it to a voltage controlled oscillator and tried to make music.

But all I ever got was noise.
Post by Sarr J. Blumson
--
--------
http://www-personal.umich.edu/~sarr/
Larry Elmore
2005-05-21 00:19:19 UTC
Permalink
Post by Sarr J. Blumson
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.
Obviously not someone who ever had to debug sitting at the console and
pressing buttons to step through a program one instruction at a time and
watch what was happening by watching the lights.
Some of us have even had the experience of standing and staring at the
lights for a few minutes and diagnosing broken hardware.
I've certainly done that with sound. When I was in the Air Force, we
still had an early 1960's relay phone switch at the site I worked at.
Only 100 lines, but occupied 7 oversized equipment racks. After a time,
you could diagnose a number of problems by sound alone.

--Larry
RM Mentock
2005-05-20 23:46:54 UTC
Permalink
Post by Larry Elmore
Post by Sarr J. Blumson
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.*
The
Post by Larry Elmore
Post by Sarr J. Blumson
Post by BobMac
Post by Lee Ayrton
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.
Obviously not someone who ever had to debug sitting at the console and
pressing buttons to step through a program one instruction at a time and
watch what was happening by watching the lights.
Some of us have even had the experience of standing and staring at the
lights for a few minutes and diagnosing broken hardware.
I've certainly done that with sound. When I was in the Air Force, we
still had an early 1960's relay phone switch at the site I worked at.
Only 100 lines, but occupied 7 oversized equipment racks. After a time,
you could diagnose a number of problems by sound alone.
I can do that today, en familia

--
RM Mentock

Myths and legends die hard in America -- Hunter S. Thompson

Patrick Scheible
2005-05-20 20:01:54 UTC
Permalink
Post by John Francis
Post by BobMac
Post by Lee Ayrton
This tickles a question in my mind: In movies and television in the
1960s and 1970s, "computers" were often represented by a large bank of
small square panels that would be illuminated at random intervals.* The
harder the computer worked, the faster the blinking, the more powerful
the computer the more blinky lights. But where does that visual trope
come from? Did computers in that era actually have such displays?
When I worked briefly for the Blue Thing, the story was that they had
been added so that the customer would have some comforting indication
that something was actually happening.
When DEC introduced the third version of the PDP-10/DECSystem-10, the
KL-10, it had practically no blinky lights on the outside (and only a
PDP-11/35 console display inside if you opened up the cabinet doors).
Somebody (MIT, I believe, although it could have been BB&N) cobbled up
a display using an empty CPU cabinet from an earlier model of PDP-10,
which still had all the light panels installed. THey even labelled it
with a semi-official looking DEC part number: KL-UDGE
I've heard it explained as (U)ser (Display) in (G)raphical (E)lements,
but I don't recall that explanation being current at the time.
(I actually saw the cabinet in question, hooked up to the KL-10)
Neat. Anyone have photos? or a confirmation about where it was?

-- Patrick
Loading...