A few points:
- The BGT (Blasted Goldball Terminals) were indeed noisy, but
they did make a better carbon copy than the 327X screens.
- I wrote what was the first "teletype support" for SHARP APL,
I think in 1972 or 1973, for our University of Toronto in-house site.
Character mapping, was a nightmare, and none of us (Roger Moore
and I) were never happy with any of the schemes we used for them.
- The APL-ASCII terminals came along later, in two flavors - "bit-paired"
and "typewriter-paired", due to the terminal manufacturers' inability
to agree on anything. These were either dot-matrix terminals
or "print wheel"-based ones. I think the latter were made possible by
the advent of small, inexpensive stepping motors.
- We did have APL print trains on the 1403N1 printers with UCS.
The earlier 1403 printers, with print chains, did not have APL,
so this was A Great Advance. The print chains were not amenable
to local mods, but the trains had print slugs that you could replace,
to make a custom character set.
Bob
On 2018-06-17 04:18 AM, Ian Clark wrote:
At the IBM Scientific Centre in Peterlee we had 3270-series terminals for
APL characters from 1975, I'm pretty sure. But I learned my APL around 1973
on an EBCDIC-only 3277. No, I didn't use that absurd curly bracketed
notation – the first mainframe APL I used was APLSV, which had separate
256-byte input- and output-tables as editable text files. If you had a
spare afternoon you could customise them however you liked, and I
cobbled-up a usable APL alphabet (small-e for epsilon, small-i for iota,
etc) omitting the rarer characters like domino and covering them if needed,
or copy/pasting the character from quadAV.
When at last I was able to type real APL characters I didn't take to them
at all – I couldn't read the code.
But nobody ever read the code. APL was proud of being a Write-Only
language. But I felt the shame. There I was, able to read assembly code as
fluently as a newspaper, but I couldn't read an APL program I had just
written.
Fortunately I never had to use one of those blasted golfball terminals
which sounded like a tommy gun. They were in heavy use by our project
partners ADSS Mohansic for prototyping software (in APL) intended for the
hush-hush FS (Future-Series) mainframe. When you walked into their lab,
with a hundred APL programmers all beavering away, the noise was deafening.
In those days computers were IPL-ed daily (Initial Program Load-ed) – and
the FS prototype took longer and longer to IPL as emulation piled on
emulation (I think they were using APL to emulate the instruction set!)
Eventually it exceeded 24 hours, at which point the project was cancelled,
to great staff and customer consternation.
So the story goes.
Shortly afterward, on one of my regular transatlantic jaunts, I referred
airily in conversation to an "Iverson Ball". My interlocutor, a born-again
evangelical, curtly informed me it was called the Iverson Printing Element.
Ian
On Sat, Jun 16, 2018 at 10:26 PM, Don Guinn <[email protected]> wrote:
Other problems. Never heard of a print train with APL characters for high
speed printers. Had to have a special type ball for Selectric typewriters.
It wasn't until the late 1970's that teletype matrix terminals started
supporting APL characters. Likewise for 3270 monitors.
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Robert Bernecky
Snake Island Research Inc
18 Fifth Street
Ward's Island
Toronto, Ontario M5J 2B9
[email protected]
tel: +1 416 203 0854
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