DD               Define doubleword                                  Directive

  [name] DD [type PTR] expression [,expression] ...

    Allocates a doubleword (4 bytes) of storage. name is the symbol
    you'll subsequently use to refer to the data.

    type followed by PTR adds debug information to the symbol being
    defined, so that Turbo Debugger can display its contents properly.
    type is one of the following: BYTE, WORD, DATAPTR, CODEPTR, DWORD,
    FWORD, PWORD, QWORD, TBYTE, SHORT, NEAR, FAR, or a structure name.

    expression can be

        - a ? (question mark)
        - a duplicated expression (DUP)
        - a constant expression in the range -32,768 to 65,535
          (if 80386+ selected: -2,147,483,648 to 4,294,967,295)
        - a relative expression or address that requires 16 bits
          or fewer (32 bits or fewer if 80386+ selected)
        - a relative address expression consisting of a 16-bit segment
          and a 16-bit offset
        - a string of up to 4 bytes in length, using standard quoted
          string format
        - a short (32-bit) floating-point number

    Examples:   typ     DD      "ObjA"
                i24h    DD      _TEXT:offset new_i24h
                d1      DD      1.28E+5         ; Floating point
                d2      DD      12345678r       ; Real number (hex)