Re: abbreviations

Hi Peter,

What's in a name? I guess "TTY interface" must be the REAL McCoy! "TTY
style interface" is meant to mean (at least by me) the interface designs
derived from the original use of a TTY as an output device (yeah, my old
PDP8E and my first Altair computers). DOS could be said to be
"inspired" by OS-8 (DEC operating system for the PDP8), or any of the
other, similar operating systems popular in that era.

When it became possible to use a CRT with an "addressable screen" (as
opposed to "glass TTY's, which ONLY displayed a line and scrolled up)
also called "dumb terminals" for display, interface designers had the
option of "keeping" info on a screen, and of using typically a 24 line x
80 column presentation of data, rather then having to write 24 lines of
72 or so characters to the TTY each time ONE thing had to be changed on
the "screen". Suddenly, it's not a "one line display", but 24 lines (or
whatever)!

MORE COMMENTS BELOW:

cadcamcenter wrote:

>
> --- In CAD_CAM_EDM_DRO@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> > Hi Peter,
>
> > A "TTY interface" is meant to describe a single line of text sent
> to an
> > output device at a time. DOS command line command is an example.
> Hmmm,
> > sounds like Gcode's "blocks". Gcode started out on TTY's (my first
> > "consulting" job. Yeah, that was a while ago).
>
> Is there a difference between TTY interface and TTY style interface?
>
> That old black screen with a series of lines of white text, where one
> enter text like
>
> c:\autoexec.bat [enter]
>
> or
>
> c:\cd a: [enter]
>
> etc
>
> is TTY interface?

Yes, EARLY CRT's were just "glass TTY's", and were treated this way.
Some responses may use more then one line to display, say, a table, but
until the "screen" stays put and data is simply updated in the various
places on the "screen", I'd still call 'em "Glass TTY's" or "TTY style
interfaces".

>
> TurboCNC, DeskNC, CNCPro etc where one may press some button to
> execute some command, eg, pressing [L] to jog left and [R] to jog
> right. This is TTY interface/TTY style interface/both?

Actually, the keys used to execute something have nothing to do with
being TTY style interfaces. It's the screen presentation that counts!
These are just "short cut" keys, used instead of typing "move left" or
something like that on a keyboard. A set of keys is agreed upon to
denote special functions.

These programs, (even my STEP4), are using an "addressable screen" (for
lack of a better name) or perhaps APA "All Points Addressable", when we
move from a text mode screen to a graphics mode screen. That's why the
XYZ coordinates displayed on the screens of these programs are updated
(sometimes on the fly) quite often. Imagine what things would look like
if you had to print out a new line on a TTY for X, Y, and Z each time
they were updated! And all the other changing parameters! LOTTA PAPER
(can be useful in debug, as an "audit trail")!

>
> DeskNC for windows, FlashcutCNC, Master5, Acad. These are GUI's
> Are the provisions for entering commands like in MDI within the GUI's
> (if there is such a thing)

These "Windoz programs" are using a GRAPHICS mode for the screen. These
are, for example 800 x 600 pixel displays, as opposed to 80 x 24
CHARACTER displays (the video board does this for us). GUI's (Graphical
User Interfaces) usually imply graphics of some sort. Text in boxes,
round buttons, "sliders", scalable "STROKE FONTS" (text is "drawn" in
terms of pixels instead of character row/col position), and other little
widgets. MDI has NOTHING to do with being a GUI; TurboCNC, STEP4 and
other DOS program (text screen) UI's have them! A program can have a
"command line" interface available (which is what MDI's are) whether
they are GUI's or not.

>
> MDI: G01 Y1 F20 [enter]
>
> or the Command Bar in Acad
>
> Command> Line [enter]
> Command:First point> 3,4,0 [enter]
>
> are they TTY style interface?

Yes, that single "command line" or small window of lines could be
considered a TTY style interface, if you like. "file, run" in Windoz
3.1 offers you a single "command line". "start, run" in Windoz 98 also
offers you a similar single line command entry.

Under the hood, a controller program with a GUI operates essentially the
same as a program that employs a text screen for a UI. Now whether the
program runs on DOS or Windoz, THAT's another thing!!


HTH

Alan KM6VV
P.S. More abbreviations for you!

>
> Thanks
>
> Peter