PRESET Statement Programming Example
 
This example uses PSET and PRESET to draw a line 20 pixels long, then
move the line across the screen from left to right.
 
SCREEN 1 : COLOR 1,1 : CLS
FOR I = 0 TO 299 STEP 3
    FOR J = I TO 20 + I
        PSET (J, 50), 2         'Draw the line in new location.
    NEXT
    FOR J = I TO 20 + I
        PRESET (J, 50)          'Erase the line.
    NEXT
NEXT