Diomidis Spinellis <dds(a)aueb.gr> wrote: |In the late 1970s or early 1980s I worked over a summer in a repair shop |for equipment manufactured by the German company Kienzle Apparate GmbH. |Their keyboards were a marvel of electromechanical engineering. When a |key was pressed the remaining keys were *physically locked*, preventing |a second key from getting pressed. This was supposed to provide the |operators with tactile feedback when they accidentally pressed more than |one key. Maybe gratuitous over-engineering, such as this, contributed to |the company's decline and the eventual takeover by Manessmann (1981) and I think you mean Mannesmann. (But man-eat-man is indeed nice, though the hectical meltdowns and incorporations of entire companies for a little bit of revenue for unknown reasons is pretty common. Maybe cutting off history might be an idea, the Khmer Rouge went the same direction, did they. (Really correct would be manissmann/manißmann, then, as in man-eat!-man...)) |then DEC (1991). I wish Christians a nice Easter feast. --steffen

George Ross scripsit: It's true that CR takes longer, but you have to send both CR and LF because CR only returns the carriage whereas LF only feeds lines. Skipping to the bottom of a page was done by sending pure LFs, whereas underlining was achieved (though the 33 had backarrow rather than underscore) by sending a line of text followed by CR followed by a line of spaces and underscores. Later, when it was observed that this made the text illegible on glass TTYs, the order was reversed: spaces and underscores, then CR, then text. It may have been the Olivetti. -- John Cowan http://www.ccil.org/~cowan cowan(a)ccil.org Consider the matter of Analytic Philosophy. Dennett and Bennett are well-known. Dennett rarely or never cites Bennett, so Bennett rarely or never cites Dennett. There is also one Dummett. By their works shall ye know them. However, just as no trinities have fourth persons (Zeppo Marx notwithstanding), Bummett is hardly known by his works. Indeed, Bummett does not exist. It is part of the function of this and other e-mail messages, therefore, to do what they can to create him.

All this talk about Teletypes brings up memories. Model 33 TTY's were single case and each "key" (which was tubular) had to be pressed down over 1/4 inch to register. It was a significant effort. The model 37 TTY's that came along a few years later were upper and lower case (Unix was one of the few OS's at the time that could handle both cases smoothly). But if you opened the case, what was in it was an astonishing assembly of cams, levers, and other mechanisms. When glass TTY's came along, they took over quickly. One of my most vivid memories of "paper" TTY's happened at my home, early in my Unix experience. The TTY had a box of paper feeding it, and the output was also allowed to pile up behind it. This "used" paper served a critical role. At the time, Unix had two kinds of files -- small and large -- and if the system crashed (not uncommon in those days) when your file was in transition from small to large the contents of the file were lost. It was also frequently the case that updates were lost in files being edited. So when the system crashed, you would haul up the terminal output and highlight the changes that you made in case you needed to enter them again. This typically took a few minutes, by which time the system was up again and you could start to reenter your changes. So one day, I was heavily into editing when my wife, in the kitchen, needed help with the kids so I went to help her out, leaving the terminal running. It was several hours before I was able to get back to it, at which point I discovered that not only had the system crashed, but our cat had discovered an alternative "litter box" behind the terminal and made use of it! Luckily, it was pretty dry by then, but that didn't help the smell. And, so help me, holding my breath I marked the lines that needed to be reentered... The other TTY story that surfaced happened to Dennis. He had one of the last model 37's as his home terminal, and it was getting quirky. The vibration of the mechanism occasionally caused a blank space to be generated that he hadn't typed. In those days, it was common to delete the .o files after compiling because disc space was precious. So Dennis typed "rm *.o" and Unix replied ".o not found".

I picked up a Model 37 (ASR) for nothing at one point. It was sitting in my kitchen and amusingly it was probably the only terminal that I didn’t have to turn on the nl->crlf mapping in terminal driver. It also handled all those ESC and SI/SO codes that nroff put out for default to do partial line spacing and shifting from the normal roman to the greek letter typebox. I also liked the fact that it used the full RS-232 modem control lines. When the modem came online and asserted DSR it then turned on the motor. When carrier detect came up a big green PROCEED light lit up. The paper tape unit was a huge side car unlike the little integral one in the model 33. At 150 baud it was really more of a curiosity at the point I had it.