Int 2F Fn DF00  - Hyperware Programs - Installation Check                  [c]

   AX = DF00h
   BX = product code
       4248h ('BH') HyperStb
       4448h ('DH') HyperDisk v4.20+
       4B48h ('KH') HyperKey
       5348h ('SH') HyperScreen
   CX = 0000h
   DX = 0000h

Return: AL = status
       00h not installed
       FFh multiplex number in use
       CX = 5948h ('YH') if selected product installed
       ---HyperDisk---
       BX = code segment of resident portion
       DX = HyperDisk local data version
Program: HyperDisk is a shareware disk cache by HyperWare (Roger Cross)

Note:  AH=DFh is the default; if it is already in use by some other program,
     HyperWare programs then scan multiplex numbers from C0h through FFh

See Also: INT 13/AX=8EEDh
Index: installation check;HyperDisk|installation check;HyperStb
Index: installation check;HyperKey|installation check;HyperScreen
Index: HyperDisk;installation check|HyperStb;installation check
Index: HyperKey;installation check|HyperScreen;installation check