AT&T 6300 Programmer's Manual page 423

Syntax
x,y
color
Remarks
Examples:
PSET
Statement
Illuminates a pixel at a specified position on
the screen. (Graphics Mode only.)
PSET [STEP] (x,y) [,color]
If the STEP option is not included, x,y are absolute
coordinates of the point to be drawn. If the STEP option is
included, x,y are the relative coordinates of the point to be
drawn.
is the color number to be used, in the range 0 to 3. (See the
COLOR graphics statement for the current screen mode, for
details.) If no "color" parameter is given, the graphics
foreground color is selected.
PSET differs from PRESET in the default if
no color is specified. PSET defaults to the
foreground color. PRESET defaults to the
background color.
See PRESET.
5 REM DIAGONAL LINE
10 FORi=OT0100
20 PSET [i,i]
30 NEXT
10 REM CLEARS OUT LINE BY SETTING
EACH PIXEL TO 0:
40 FOR i=100 TO 0 STEP-1
50 PSET [i,i],O
60 NEXT
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