Selects the specified display as the current instruction display.
    This causes the output of all EXAMINE/INSTRUCTION commands to
    go to that display. The display specified must be an instruction
    display.
    If you do not specify a display, the current instruction display
    is unselected and no display has the instruction attribute.
    By default, for all languages except MACRO-32, no display has the
    instruction attribute. If the language is set to MACRO-32, the
    INST display has the instruction attribute by default.