Miscellaneous Operating Systems/Hardware

No, not Bjorn, the other one ... from Wikipedia :

Another odd feature of the Selectric terminals was the "keyboard lock" mechanism. If the system a user was communicating with was too busy to accept input, it could send a code to mechanically interlock the keyboard so the user could not press any keys.

"You will type at my speed or you will not type at all. Is that perfectly clear ?"

/s/ your Computer

I think of it as an elegant solution to the common guessing game called "did the machine buffer the keys I just typed, or were they flushed?"

I think the Teletype ASR-33 does something similar, it looks the keyboard until the character is sent. So if you type faster than 110 baud... you would probably be annoyed

How fast can anybody punch those goofy round keys? Where did an experienced operator top out on one of those horrid keyboards?

NO IT DOES NOT STOP A 43 I DON'T KNOW NEVER HAD ONE STOP BUT WITH A 33 YOU HIT THE KEY AND IT CLANKED THE PAPER JUST LIKE A MECHANICAL TYPE R WRITER STOP YOU CANT HIT THE NEXT KEY UNTI;L THE FIRST KEY COMES BACK UP STOP THERES A BUNCH OF RODS AND LEVERS CONNECTING THE KEYS TO THE PUNCHING THINGY IF YOU HIT MORE THAN ONE AT A TIME THE MECHANISM WILL JAM STOP


THE ONES WITH ABOUT AN INCH OF TRAVEL ? 3 CPS ROUGHLY STOP THATS IF YOU DONT MAKE ANY MISTAKES STOP IF YOU MAKE A MISTAKE YOU HAVE TO BACK UP THE TAPE AND OVERPUNCH THE ERROR WITH A NULL SIGN STOP THAT A TAKES AT LEAST A MINUTE STOP THE PENALTY FOR ERROS IS LARGE SO GO SLOW AND CAREFUL IS T T HE WORD WORD BIRD IS THE WORD STOP

THEY WERE STILL BETTER THAN THE FRIEDEN FLEXOWRITER STOP FLEX R OWRITERS ARE NOT EVEN GOOD FOR WEIGHTING DOWN THE TRASH CAN STOP I SERIOUSLY LUSTED AFTER THE AD D M-3 LIKE NEKO NOW HAS STOP


READING A TAPE, I THINK IT RAN AT SOMETHING LIKE 10 CHARACTERS PER SECOND STOP IF YOU WANTED TO SAVE TIME (AKA TIMESHARING) THEN YOUD PUNCH UP A TAPE AHEAD OF TIME AND USE THAT RATHER THAN TRYING TO SEND VIA KEYBOARD. TOO EASY TO MAKE M U ISTAKES WHILE TYPING.

I HATED THE 33 STOP COST SEVENTY-FIVE DOLLARS A MONTH TO RENT ONE AND THE EFFING THING WAS A POS STOP THEY SMEELED KIND OF FUNKY TOO STOP TO MAKE ONE TAPE YOU HAD TO PUNCH THREE THEN HOLD THEM UP TO THE LIGHT TO FIND THE MISSING OR MISTAKEN HOLE THEN USE A BALLPOINT PEN OR PIECE OF SCOTCH TAPE TO CORRECT THE ERROR STOP I LUUUUVED MY SELECTRIC III BUT THE TELETYPE WAS HORRID STOP AND THEY WOULDNT PUNCH MYLAR EITHER SO IF YOU HAD A TAPE YOU USED A LOT IT GOT ALL WORN OUT STOP PLUS THEY HAD CONTROL CHARAC H TERS AND IT WAS POSSIBLE TO ACCIDENTALLY TYPE A FO U RBIDDEN COMBINATION THAT WOULD MAKE SOMETHING STRANGE HAPPEN STOP FIGURING OUT WHAT WAS WRONG THEN W E AS A MAJOR MYSTERY SLASH HASSLE STOP

I HATED THAT POS STOP WOULD LIKE TO HAVE ONE NOW BECA S USE THEY ARE SO FUNKY BUT FOR DAILY USE THEY SUCK THE BIG ONE STOP TERRIBLE STOP

Too much Yamazaki, Hamei?

Nice job, hamei.

I'm mostly free of any urges for a real TTY. There's a tad of nostalgia because for one year every other week I used one to learn a trifling amount of BASIC one some unidentified machine that the Philadelphia school district made available. Still have the printouts on that characteristic yellow paper, somewhere.

Impressive Goldbergian devices, and certainly deserving of some respect for the role they played for decades if not for the objective quality of the design.

I have a thermal paper terminal with a 300 baud acoustic coupler. it was modified to add a serial interface for some type of minicomputer.
it's from 1971, about a decade before the popular TI Silent 700 terminals that did basically the same thing.

I guess it's only funny if you had to run one ...

Maybe a little description ... the keys themselves don't work like a manual typewriter with that nice clean swing-out action. They are round and badly spaced as sm mentioned. They also slide in a housing with round sockets, but since it's all plastic they can't have a nice smooth sliding fit, no, they have to be loose or they'd seize. So the piston-sleeve interface gets all this dirt and crap in it and they slide very poorly and it takes a lot of pressure. Clank ! clank ! clank ! for every character. The baudrate wasn't a problem for manual entry, the stinking key action was. It's all mechanical but not even nice mechanical. Ponderous would be a good description, like hitting the keyboard with a rock.

Oh. Maybe you didn't know. There's no lower case. Also the "stop" comes from either illegible or non-existent punctuation. Maybe the early ones didn't even have it ? By the seventies they did but the "stop" convention was fail-safe. Every time I see someone write somewhere with caps lock on I think "This guy is posting from a Teletype ! Cool !"

As I mentioned, the method to correct was to back up the tape, overstrike the error with a null character, then (try to) return to where you were and carry on. Or mark the tape then you could manually correct later with a hand punch and splicer. There were kits for editing paper tape by hand with a guide rail, swing-down hand punch thingy and so on. One nice thing about mylar tape tho, no bitrot. A mylar tape will probably still be good in 100 years. Or maybe more ... almost as good as a stone tablet

Most teletypes did not have a serial interface. They had a current loop which didn't communicate with anything except a telephone. Timesharing, anyone ? I did that for about six months but it wasn't worth it (to me. I spent too much time on the process and the product and not enough on money money MONEY ! The time-shared faster cheaper not-better programs were not as good as hand-written ones.)

Nowadays it would be trivial to make a converter for rs-232 but then, there was no internet. The people who knew how to take three resistors and make a converter were not forthcoming with that information. Thus $200 of 1975 money for a 1" by 3" piece of fibreglass with three components on it. A new Sportster cost $1500 in 1972. A 1978 Ford Fiesta cost $3000. My tape punch cost more than the car.

Underneath the keys is a peculiar set of binary mechanical rods and levers which, naturally, don't move smoothly either. The Selectric of the same vintage is a joy to type on, even better than a Type M clicky keyboard. A Selectric would probably make a great input device for a computer. They really are great.

So you've got this clanky-ass pos to type on which also makes mistakes. The print head is a cylinder that moves to orient the character, then a hammer with a rubber pad whams it from behind onto the paper. Sometimes it whams it too hard, sometimes it whams it too soft, sometimes the letters don't get into the exact correct spot and after time the rubber pad gets all blown up and you don't have a new one handy so the thing whams on its own type-head with a hammer, which does bad things to the type head. The paper is also this cheap yellow junk that even a throwaway newspaper would be ashamed to use. No, there are not other suppliers for better paper. It was a weird size.

Meanwhile, the crappy punch mechanism screws up ab0ut once every three feet. Yes, feet. We're talking paper tape here. Specs on controls in those days described memory capacity in feet. 400 feet of extra memory in a Bendix 5 was something like $3,000. I think that was 32k but it might have been 16k, I forget the conversion factor So what you do with an error is take the tape over to your handy-dandy editing kit and manually correct the mistake. Lots of guys in the seventies could read ASCII directly off a paper tape.

They also gave off this peculiar ozone-ey smell the whole time, too. There was about a half-horse motor in the back running constantly. (Okay, 1/2 hp is an exaggeration. But it may as well have been. It was a good 3 or 4 inches in diameter and looked like Thomas E himself designed it. )


When I finally got a Facit 4070 ( $4,000 new at the time) and an HP Vectra (they didn't have ES, RS, New Vectra, Old Vectra then it was just a $4,600 286 with a 13" color monitor) I was soooo happy. That really was good enough. We should have stopped Time right there.


You can tell how long people have been making parts by how they write programs ... FORTRAN is a nice comfortable language

N010 G90 M03 S450
N020 G92 X-13.3312 Z12.0312 M08 S1750
N030 G04 F2 T0303 (ROUGH TOOL CNMG 432)
N040 G00 X-5.5312 Z8.6312
N050 G01 Z4.75812 F.015
N060 G04 F2
N070 X-5.77 S425
N080 G00 Z8.5312 S475
N090 G01 X-5.3312 F.05
N100 Z7.5812 F.015
N110 G04 F2
N120 X5.5 S440
N130 G03 X-5.7812 Z7.3 I0 K.2812
N140 G01 Z2.5
N150 X-5.9
N160 G00 X-8.0 Z8.0
N170 G04 F2 T0505 (FINISH TOOL DNMG 432)

etc etc

Block numbers jump by ten so it's easy to insert edits. Imagine typing this clank clank clank one character at a time with an average program length of a couple hundred blocks. (Each program line is one block.) Milling programs are much larger. Can you imagine hunting down an 0 - o mistake on a five foot roll of trash yellow paper that looked like a ransom note ? I still slash my sevens because a seven - one error is really hard to find in a hand-written program. But it can make a significant difference when you are moving several hundred pounds of steel at 400 inches per minute, hopefully not into a solid object.

Oh, but first you go to do the arithmetic. HP-41 to the rescue, one triangle at a time. Lucky for me that the only math I really liked was trigonometry ...

And you know what ? I would leap back to that time in a heartbeat. Yes, all this was clunky. But the world was a much better place (or the US was, at least.) Compare the real work people did then with the slashdot crap we have today. Ajax ! Soap ! Web 3 ! Gnome ! Compiz ! Social Networking ! Flash your boobies for some bitcoins ! Hooray ! Now wer'e progressive and advanced !

gag me with a spoon ... you don't have to be a cranky old fart to read the papers these days and wonder what's the point of humanity ? Wtf do people do that makes them worthwhile ? I saw some tiger paws on the sidewalk this morning and wanted to kill the useless shit selling them. I did give them a piece of my mind (not that there 's a lot to spare but still ... ) Luckily that's very very rare or there would be a foreigner in jail. The earth would be better off without us.

A Bendix 5 control has a Control Data computer as the thinking portion. K&T used PDP-8's and later built their own, Sundstrand used a PDP-11, McDonnel-Douglas built their own (Actrion), Giddings & Lewis built their own, Cincinnati built their own, GE built a pile of crap (GE has always been second-rate shit), Allen-Badley built their own, Hurco built their own, Westinghouse built a few different nice controls between periods of going into and out of the business, there were more I can't think of at the moment.

Every single one of them was better than that useless Fanuc shit (datum point in mid-air ? Are those people insane ?) but for political reasons ( Ve vill control zee vorld ! Zee evil godless Commnists in Red China moost be controlled ! Und zee bankers are zee Important People een dis society ! Ja vohl !) the United States government let every one of them be destroyed by Kirk Kerkorian et al and the lousy rotten buck-toothed four-eyed murdering rapist Japs (e.g. Nanjing, vivisection on human subjects including American POWs, germ warfare, torture, etc etc - oh well, now we can do that because we are so special and really need to fight tewwowism so now it's okay.) And we actually gave the person responsible for those programs a free ride because the US wanted that data so we could use it in Korea. Nice. Hey Hillary ? Clean up your own overflowing toilet before you open that everflapping hole in your face, bitch. And that two-faced self-righteous cunt is going to run for president. I want to throw up.

"Let" them be destroyed ? We used to ask "How come the US doesn't have an industrial policy like Japan ?" Want to talk naive ? Boy were we stoopid. Of course the US had an industrial policy. The policy was "Crush the middle class and these saps who want to have a respectable living doing something worthwhile. Financiers are the Important People in society. They have MONEY ! We don't need no steenkin' middle class ! Look at Mexico ! Life there is so wonderful !" (for about ten people.)

Intellectual property, oh yeah. When it's Hollywood getting gored We MUST PROTECT THE RIGHTS OF THE CREATORS (e.g. Solomon Linda) but when it's some crappy rust-belt relic of the past industry like Bridgeport or Sundstrand that employed thousands of skilled craftsmen, ah fuck em, creative destruction is the strength of the kapitalist system ! Hooray, no more middle class to get in our way ! We will control the world ! This is the New American Century !

Fucking imbeciles at the top and fucking imbeciles parading along behind. All I can say is, the loser idiot middle class of the US went along with this crap for the past thirty years, so now there is no middle class. Just a bunch of whining self-righteous crybaby faggots snivelling when some of the evil they do worldwide comes back to haunt them.

The US is a stinking piece of rotting offal led by evil vicious scum. What a mess. Give me 1975 and I'll live with the Teletype.

The Model M was supposedly a "cost-reduced" version of the Selectric keyboard and the Cherry key switches are a "cost-reduced" version of the buckling-spring ones in the Model M

I have one of these keyboards . It's not a Selectric by any stretch and it looks kinda cheap, but it's well made, takes up little space, works well with SGIs, and is comfortable to type on. It looks much better if you replace the three Windows keys with blank ones


Wow, that code is really ancient
For comparison, here's how a modern Fortran program can look like: http://www.liv.ac.uk/HPC/HTMLF90Course/HTMLF90CourseNotesnode62.html


These early computers were interesting, everyone made their own CPU architecture back then

The patent applications were much more substantial that the crap that gets accepted today. For example, for the HP 9830A computer, HP put _everything_ you needed to know how to build the machine in the patent application. This includes all the schematics and even the source code for the ROMs. Here's a PDF of it: http://www.google.com/patents/US4012725.pdf .

Bah, that looks more like Ada. Real FORTRAN looks like:



... and is tens of thousands of lines long, the variable TOTAL doesn't contain the accumulated total but CURR does and functions don't do what their name suggests and has GOTOs everywhere and totally incomprehensible logic.



R.

That's interesting ! thanks ... I'm still looking for a keyboard that has the F keys in a double row down the left side. HP built them that way but HPIL she don't work with an SGI



You forgot your FINIS, Pymble

It's actually RS-274D, aka "g-code", kind of like Assembler for machine tools. Then they got "conversational" controls, which would be like writing your term paper in Postscript And it's not old, I just threw that together off the top of my head ... you can still control machine tools that way but I doubt that very many people do.

Writing programs that way sucks because it is so labor-intensive but you have total control over everything the machine does. Total. When you use a CAM system the machine cuts a lot of air, does a bunch of junk you don't really want but oh well. It was fast and easy and all I had to do was click on the various surfaces in the order I wanted them cut.

All the machine tool stuff predates personal computers and even large computers by decades. The first numerically controlled machine was running in 1952. They didn't start small and build up, either - it's more like trickle-down. This was when men built SR-71's and XB-70's with slide rules instead of taking twenty-five years and six billion dollars to buy a bridge from China - then bolt it together with bad fasteners. It will be funny when the Bay Bridge falls down ... I read what they did and go, "WHAT ! Nobody with an IQ over thirty would do that !"

But they did.

Automatically Programmed Tools, the One True APT :


Looks simple and it is but it will do geometry up the wazoo. APT predates FORTRAN It was the first ANSI standard. Somewhere around 1964 they rewrote it in FORTRAN ... and it will still do some things that graphical point-n-click CAM programs cannot. I have APT/360 code (public domain) if someone wants to help get it running in Irix .... it's fun to play with (if you don't have to make the rent with it.)


And the more architectures you have, the more ideas and the more choices ... as long as everyone can run on the same roads, a lot of different cars is a good idea. That was the Loonies' rallying cry back when they were the underdogs


You could build your own PDP-8 from the prints that came with a K&T. Honest, the machine came with full prints to the boards and K&T built three boards of their own that went into the PDP-8 for real-time control and they wrote their own operating system. Not "sort-of" real-time, realtime. Sundstrand likewise. And when you called tech support, you got someone who knew their shit. No one from India ! Some of those guys could think in binary. Seriously. It was nice to talk to people who knew their job. Knew it inside-out, frontwards and backwards, and never once said "Oh we can't tell you that, it's a seeecret !" Gag.

But hey now, it really is more important that Mark Zuckerberg has eighty billion dollars in the Caymans than the US has an industrial base, right ?

I would not be surprised if the US collapses within the next ten years. You simply can't run a country on hot air.

Here's a photo of the Teletype keys, better than my description. You can see why they would have a terrible action :


And the site I stole it from has a great description of how they work - it's "innovative"

http://www.oldcomputers.arcula.co.uk/perf1.htm

not as elegant as a Brunsviga...

Per LC (Library of Congress) librarians, punched Mylar tape is still the best choice for long-term archiving of information. It does not rely on proprietary or difficult-to-build reader mechanisms and does not degrade when stored properly.

The Library of Congress would have to be as large as Indiana to store much The K&T D control could have as much as 192k of memory. A lot of it was for part program storage tho. The executive program probably fit into about 40k. It took over twenty 8" reels overflowing with tape to load. That's a stack almost chest-high ... Paper tape is fun tho. It's much more tactile than a floppy disk.

This is so off topic, I love it :)

related to the Library of Congress and paper tape as a storage medium:
http://www.kinetta.com/download/files/K ... canner.pdf

Nothing is too off-topic for us


Very very cool and looks like a nicely-made product

However ...


Not new, Decitek readers used a similar system in 1980


Sorry, can't be unvarying. As the film on the reel gets smaller the path changes. May not be much but the claim cannot be true.

Also, the "dancer arms" on a Remex reader were not simple spring-loaded devices to put tension on the tape. They had an analog potentiometer connected to the arm to measure the diameter of the tape on the reel. As the diameter got smaller the reel on that side spun faster (variable speed dc motors were used) to achieve the same linear speed. And vicey-versey on the other side, natcherly.

I had both Decitek and Remex readers - in practice, the Remex performed better.

I also had a Tallyreader or two which were mechanical. They sounded like very small-caliber machine guns for miniature armies People bitched about the mechanical readers but in practice, I had less trouble with the Tallyreader than the nice optical devices.

Look at the Portability page ... some nice behind-the-scenes shots of the Nixons' lives. Never thought I'd feel nostalgic for Tricky Dick ...

not sure on the exact design, but from the description of the prototype the rollers do move slightly and use a hall effect switch to detect film tension. so the "dancer arms" are present, just with very short action. It seems like an attempt to contrast the design to a Geneva loop.

There's this HP-HIL to PS/2 adapter , but it's very expensive.


I've always wanted to build my own PDP-8/S
The PDP-8/S is interesting because it had only 519 logic gates and its CPU processed only 1 bit at a time instead of the full 12 bits (it was slow, but physically small-ish).
If somebody has any links to a schematic for it (preferably using new CMOS/TTL SSI/MSI logic, not individual transistors), please let me know =)

Most of the old equipment I've seen was also designed to be serviced, so there are many extra markings & test points on the PCBs, and dedicated service manuals etc. Now it's just expected to throw the entire thing away and buy a new one if a single capacitor fails

The build quality of most new devices is also very bad. I managed to save an HP 9830A , built in 1972, from being thrown away (however, those idiots threw away the plotter before I could get to it ). The machine is over 40 years old and is _still_ working perfectly! I bet no electronic device made today will last that long.

I could get you two complete computers, a tape punch and a 2' x 2' x 4' plywood box of spares if you wanted to ship them from China