The NEXT LINE key (0) is used to  move  the  cursor  to  the  next  or
 previous line on the screen.  If the default movement direction of the
 cursor is ADVANCE, the cursor is moved to the next line on the  screen
 (same  as  DOWN  ARROW key).  If the default movement direction of the
 cursor is BACKUP, the cursor is moved to  the  previous  line  on  the
 screen (same as UP ARROW key).

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