Scroll


Purpose   Scrolls text on the screen in any of the four directions.

Decln.    Scroll(Way:direction;X1,Y1,X2,Y2:byte);

Remarks   Way is the direction to scroll the text. The valid directions are
          Up, Down, Left and Right.
          X1, Y1 are the coordinates of the top left corner of the region
          to be scrolled.
          X2, Y2 are the coordinates of the lower right corner of the
          region to be scrolled.

          One line or column of text is removed, and a new blank line is
          inserted.

Example

BEGIN
    SCROLL(UP,1,1,40,25);
END;

The left side of the display screen is scrolled up one line. The top line
of the text disappears, and a new blank line is added at the bottom of the
screen.