
Emulation of Unix V6 on a PDP-11 with an emulated teletype - beefhash
https://pavel-krivanek.github.io/pdp11/
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kps

        NICE DEMONSTRATION OF WHY KEN DIDN'T SPELL CREAT() WITH AN 'E'.

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ajross
Yeah, though this feels artificially slow to me. Even the earliest Teletype
machines could manage 10+ cps, and by the mid-70's time frame (v6 was released
in 1975) much faster devices were available (and of course video terminals
were starting to arrive too).

I'm sure someone used a PDP-11 with a terminal this slow, but it's unlikely to
have been the typical developer experience.

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davidgould
I used a PDP-11/70 with ASR-33 TTYs as late as 1978. They were still common
because while slow and noisy they were much cheaper than the DECwriter, and
could also read and punch paper tape. Since mass storage was very expensive
(10MB for $20,000) and since floppies were not yet common, paper tape was the
USB stick of the time.

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tyingq
The pidp-11 project is also cool. A miniature and functional PDP-11 replica.
[https://obsolescence.wixsite.com/obsolescence/pidp-11](https://obsolescence.wixsite.com/obsolescence/pidp-11)

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scroot
Ok but let's be honest: Unix is at it's core still a teletype emulator no
matter where you use it. It's the central metaphor for the system.

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Koshkin
Well, UNIX "at it's core" is the kernel; what you are talking about is what is
known as 'shell.'

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johnlorentzson
UNIX and everything surrounding it is built around the shell though.

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fortran77
This is very nice. Brought back old memories of my first programming Fortran
and BASIC+ on RSTS/E on a PDP-11

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flyinghamster
You, too? My high school had an 11/34 back in the day, with a couple VT100s,
several Visual 200 terminals (cheap junk), one DECwriter II for the console,
and another one plus a DECwriter III in the lab. It also ran RSTS/E, and in
the summer after my sophomore year they offered a short introductory course. I
was hooked. We didn't have any Fortran courses, though, just BASIC+ and COBOL.

I'd take even a DECwriter II over a Teletype, but the III made the II look
downright slow, with a 4x faster printhead, the ability to seek quickly, and
the ability to print in both directions to avoid wasted motion.

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phoe-krk
The point where I burst into giggles was when I realized that scrolling the
page while output was still going (e.g. from ls /bin) overwrote previous lines
with new letters.

That's some dedication to accuracy that's found there.

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davidgould
Don't try to use ^S and ^Q for flow control, it doesn't work and the ^Q will
quit Firefox. As a tab horder, I hate quitting the browser.

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Koshkin
Just remember to type CHDIR instead of CD.

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saagarjha
Did teletypes not have rollover? The most annoying part of this was waiting
half a second after each keypress…

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DonHopkins
Teletypes have metal rods and springs instead of rollover!

I love how the mouse wheel (back in reality) scrolls the paper up and down and
it overprints.

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saagarjha
But typewriters (at least the one I have tried–I think it was a Selectric?)
have the same thing and can support rollover…

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kps
The Selectric didn't really do rollover, but it had a mechanism that felt like
it. Each key lever had a small tab that entered a trough of ball bearings that
had just enough slack for one tab. If you pressed a second key, it would
displace the balls and descend when the previous key withdrew.

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pfdietz
If it doesn't smell like a teletype it isn't a true emulation.

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twknotes
backspace not invented yet? How can you write a program with this thing!

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kps
Backspace _had_ been invented; the problem is that on a printing terminal you
end up with an illegible mess. So early Unix defaulted to erase '#' kill '@'.
You can still see artifacts of that choice — ‘#’ being popular for things that
start a line, like comments and C preprocessor commands, and ‘@’ being the
only ASCII punctuation with no function in any common Unix tool.

