VMS Help TCPIP Services, TELNET, TN3270 Keyboard Functions, Up/Down Arrows  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    VT100: Up arrow or Down     VT200: Up arrow or Down arrow
    arrow
    DEFINE_KEY Function: UP, UP_NOWRAP, DOWN, or DOWN_NOWRAP

    Moves the cursor vertically on your screen without altering the
    data you have already entered.

    If the cursor is at the:

    o  Top of the screen when you press the up arrow, the cursor
       appears in the same column at the bottom of the screen

    o  Bottom of the screen when you press the down arrow, the cursor
       appears in the same column at the top of the screen

       If the screen display you receive is larger than 24 rows
       deep, you can use the Up arrow and the Down arrow keys to
       move through the display. These keys scroll the screen display
       up or down.

       If you want the cursor to wrap to the opposite edge of
       the display, use the key sequence EXT + Up arrow or
       EXT + Down arrow.