Int 10 Fn BF10  - Video - Compaq Extensions - Get High Address Map Regist  [b]

   AX = BF10h

Return: CF clear
   AX = current value of high address map register

Notes: supported by at least the QVision board and the SystemPro XL and LTE
     Lite ROM BIOSes
   the Compaq QVision documentation (October 1993) says the value is
     returned in BX, but this appears to be one of many typos

See Also: AX=BF0Fh