Int 15 Fn DA99  U - Ami Pci Bios - Get/set ??? Flag                        [-]

   AX = DA99h
   CL = subfunction
       00h check if ???
       01h set ??? flag
       02h clear ??? flag

Return: CF clear if successful
       AH = ??? (00h,01h)
       AL = 00h
   CF set on error
       AH = error code (86h unsupported subfunction)

Note:  the flag is stored in bit 0 of CMOS RAM location 2Ch for BIOS
     v1.00.05.AX1