> On Dec 14, 2015, at 11:55 AM, Paul Koning <paulkon...@comcast.net> wrote: > >> On Sat, Dec 12, 2015, Mike wrote: >> The one question I do have for the older gentlemen on here is what in the >> world did the computers without a screen to look at do? Now I know about the >> tape, cassette tape's and even the paper with the hole punches in them but >> what kind of applications were they use for? Mathematics or? ? ? > > > I'll add my perspective. My first exposure to the use of computers came from > my father, who was a mechanical engineering professor at TU Eindhoven, doing > precision measurement. He used the university's computer (there was a single > computer serving most of the university's needs) to do analysis of the test > results. For example, one instrument was an interferometer, which would > measure positions in terms of wavelength (1/8th of the wavelength of a very > stable helium-neon laser). Those measurements were punched on paper tape by > custom hardware, along with temperature and humidity observations. The > software would read those numbers, adjust the measurements to account for > temperature (which changes both wavelength and the size of the test object) > and humidity (which affects wavelength). The results could be printed, but > often would be shown graphically using a plotter (drum plotter). > > A plotter is a pretty simple device, involving a pen that can move across > paper in X and Y directions, usually with stepper motors, and a solenoid to > raise or lower the pen. Some had multiple pens (different color or size). A > "flat bed" plotter has an X/Y carriage moving over a flat table on which the > paper is mounted. A drum plotter has a carriage for one axis moving along a > drum a few inches diameter, which transports paper (a long roll) in the other > direction. > > This stuff used the "THE" operating system, an early multi-process operating > system and the first to use rigorous design for correctness and clean > structure. User input was via paper tape, for programs and data; output > could be paper tape, line printer output, or plotter output. There were some > magnetic tapes as well, I'm not sure how those were used. The OS used a > magnetic drum (similar to a disk drive, older but for those days quite fast) > for virtual memory (code and data) and for buffering I/O data streams for > paper tape, printer, and plotter. > > paul >
Thank you Paul for that reply I have learned more about the history in the short time I have been on here than I have if I would have spent 10 bagillion dollars in collage I'm just a busted up old welder now but I wet to collage for that and it was not cheap I could not even fathom what it would cost to have a teaching degree in computer science.... Again thank you very much for your input you a humble me greatly and I have the highest respect for all the pioneers of the computers rocky road some of you have went down.
