RBBS in a Box Volume 1 #2/RBBS_vol1_no2.iso/add2/suggest.zip/SUGGEST.DOC

Text File | 1986-11-09 | 6KB | 96 lines

                     The Power of Suggestion
  (PC Magazine Vol 5 No 20 Nov 25, 1986 by Michael J. Mefford)

     SUGGEST.COM is a resident program that allows you to flash
supraliminal messages in the background while you do your work.
Taken literally, subliminal means "below threshold" and supraliminal
means "above threshold."  When SUGGEST flashes your message on the
screen, it is very fast but not completely invisible.  In most cases
you will be able to read the message or at least perceive the flash.
This is really in one sense an advantage.  It lets you play around
with almost-subliminal suggestion without the possible potential for
abuse involved in displaying messages completely without one's
awareness.  The minimum "on" time for your messages is controlled
primarily by the design of the monitor rather than the design of
SUGGEST.
     To use SUGGEST.COM, from the DOS prompt simply enter:

SUGGEST message[/Fn][/Dn]

     Your suggestive message may be up to 80 characters in length;
longer messages will simply be truncated.  The /F and /D switches are
optional.  If used, n is replaced with a number from 1 to 9.  The /F
switch changes the frequency with which your message is displayed; the
larger the number, the more frequently the message pops onto the
screen.  For each increment of the frequency number, an additional 3
minutes is subtracted from the default rate of once every 27 minutes.
Actually, it's 27 minutes and 5 seconds.  Subtracting 3*9 minutes from
the 27 leaves the highest repetition rate, which is once every 5
seconds.  /F8 displays every 3 minutes, /F7 every 6 minutes, /F6 every
9 minutes, and so on.
     The /D switch changes the duration for which the message is
displayed.  The larger the number, the longer the message-on time.
The briefest flash is obtained from the default /D0 and is
approximately 17/1000 of a second.  Each higher integer adds that
much more to the display-on time.  For example, to cause the suggestion
"Think positively" to appear once every 15 minutes for 17/200 of a
second, you would enter:

SUGGEST Think positively/F4/D4

     Your message will be displayed only in 80-column text mode.
SUGGEST was meant to be installed only once, though no harm will be
done if you choose to install more than one message.  No provision has
been made to disable or uninstall, so you must reboot to either change
or remove SUGGEST.
     The first time that SUGGEST is run it gets and stores the vector
of the current timer tick routine and replaces it with the segment and
offset of SUGGEST.  Thereafter, SUGGEST is serviced with every tick of
the clock -- 18.2 times a second.  Upon subsequent entry, SUGGEST
increments a counter.  When the count equals the time-out -- 27 minutes
by default or one of the nine time-outs set by the frequency switch --
SUGGEST resets the counter to zero and prepares to display the message.
     First, the current middle three rows of the display are retrieved
and stored.  Next, your message is displayed in the middle row, with
the upper and lower message-framing rows filled with spaces.  If a
delay was added with the duration switch, SUGGEST pauses before
restoring the screen.  Control is then passed back to the old timer
tick routine.
   Studies have shown that in order to make a message truly subliminal,
its display duration should be close to 1/1000 of a second.  To study
the effects of subliminal messages, experimenters use a tachistoscope
-- a box capable of displaying images at this high speed.  PC monitors,
on the other hand, are refreshed from top to bottom every .017 seconds
-- that is, 60 times a second.  This is where the 17/1000 duration
constant came from, which becomes the limiting factor for flashing
the message on your monitor and replacing it with the original screen
data.  It takes approximately 4/1000 of a second to display three rows
on the screen.  If the three middle rows are scanned immediately after
they are put in the screen buffer and are then replaced with the
original data, an 8/1000 of a second will have elapsed.  However,
another 9/1000 of a second must elapse before the original data is
scanned.
     Indeed, you can actually observe the raster scan.  If you choose
the /F9 switch (5-second frequency), you will notice that occasionally
the message seems to be skipped.  This is because the timing of the
scan and the moving of the message into the screen buffer are such
that the message never gets scanned before it is replaced with the
original screen data.  Even more interesting is what happens when the
line that we are placing on the screen is the same line that the
monitor is scanning.  Then as we place each character in the buffer,
the electron gun moves down another scan line and only a part of our
message appears.  And it appears as a wedge.  This happens only with
the duration default of no additional raster scans.
     In addition to the raster scan time, if the message is being
displayed over spaces when the spaces are restored to the screen,
"nothing" is written over the message and a latent image can be
observed.  This latent image is produced by the phosphorous recovery
time.  This glow effect is the reason the monitor does not flicker.
For our purposes, however, it simply adds one more limitation on our
ability to control the display time.  The increase will differ with
monitors, the older models having longer recover times.
     The net effect is that SUGGEST displays very short supraliminal
messages rather than subliminal messages.  Experiment with them and
see how they work.