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The PLATO Architecture
PLATO is designed to be extremely responsive to keys. Every
keypress is processed individually by the central mainframe, but
the response (or "echo") is usually so fast as to appear
instantaneous. An echo time of 100 milliseconds is excellent;
anything over 250 is considered unacceptable.
This is vital, especially because displays do not appear
instantaneously. Originally, all PLATO terminals communicated at
1200 bps. At that speed, a long posting in Notes might take up
to 10 seconds to fill the screen. But a single keypress aborts
the display and moves on if the first line or two of a note
doesn't spark your interest.
The ability to abort pending display output is crucial. Even now
that faster connections are possible, connecting through a
network that does not permit aborting output makes PLATO feel
maddeningly sluggish.
Copyright © 1994 by David R. Woolley
Copyright (c) 1996 - 2006 Elizabeth Mattijsen
I appreciate comments, suggestions and bug-reports.
Please send these to liz-comments@dijkmat.nl.
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