Int 2F Fn D201  - Quarterdeck Rpci - Get Qd Himem Presence                 [m]

   AX = D201h
   BX = 4849h ("HI")
   CX = 4D45h ("ME")
   DX = 4D51h ("MQ")

Return: BX = 4F4Bh ("OK")
   ES:DI -> HIMEM entry point

Note:  AH=D2h is the default multiplex number, but any value in the range
     D2h-FFh and then C0h-D1h may be used (see AX=D200h for details)

See Also: AX=D200h,AX=D201h/BX=5145h