; GRBLINK
;---------------------------------------------------------------
;! Verb which blinks 2 TV graphics planes
;# VERB TV ANALYSIS
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
GRBLINK   LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
GRBLINK:  Verb which blinks 2 TV graphics planes
GRCHAN          0.0         7.0    1st graphics channel to use
GR2CHAN         0.0         7.0    2nd graphics channel to use
            Cursor X gives rate, cursor Y gives ratio, any button
            exits.
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GRBLINK
Type:  Verb
Use:   To compare graphics planes of the TV by blinking them.
       While blinking: the cursor X position controls the blink
       rate, the cursor Y position controls the proportion of
       time spent on each plane, and any button causes the verb to
       quit.  Note that 2 graphics planes may be displayed
       simultaneously on the screen (i.e. GRCH = 12; GRON) and will be
       displayed in a complementary color where the 2 agree (for
       planes 1-4, lower numbered plane shows for planes 5-8),
Adverbs:
  GRCHAN.....Selects graphics channel for "channel A"
  GR2CHAN....Selects graphics channel for "channel B"
             Either out of range -> use 1 and 2.
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