Int 2F Fn 0801  U - Driver.sys Support - Add New Block Device              [D]

   AX = 0801h
   DS:DI -> drive data table (see AX=0803h)

Return: AX,BX,SI,ES destroyed

Notes: moves down internal list of drive data tables, copying and modifying
     the drive description flags word for tables referencing same physical
     drive
   the data table is appended to the chain of tables
   supported by DR-DOS 5.0

See Also: AX=0803h