VMS Help SET, HOST, /LAT, Qualifiers, /FRAME  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /FRAME=n

    The /FRAME=n qualifier allows a user making a LAT connection
    to a remote system to specify the number of data bits that
    the terminal driver expects for every character that is input
    or output. The value of n can be from 5 to 8. The default
    value depends on the settings for the terminal established by
    the /PARITY and /EIGHT_BIT qualifiers. The following example
    specifies a character frame size of 7 bits per character:

    $ SET HOST/LAT /FRAME=7 DIAL_OUT_SVC