B, W, L, G, I, or S must precede ^ for operand number operand_number
    Facility: DEBUG, VMS Debugger
    Explanation: You must specify the type of offset as either B
    (byte), W (word), or L (longword). You must specify the type of
    literal as either I (immediate) or S (short). You may specify the
    addressing mode as G (general).
    User Action: Enter the instruction again, specifying the operand
    using one of the above modes.