Int 31 Fn 0801  P - Dpmi 1.0+ - Free Physical Address Mapping              [E]

   AX = 0801h
   BX:CX = linear address returned by AX=0800h

Return: CF clear if successful
   CF set on error
       AX = error code (8025h) (see #2814)

Note:  should be called at end of access to device mapped with AX=0800h

See Also: AX=0508h,AX=0509h,AX=0800h,INT 21/AX=EB03h