INT 15 - Compaq EISA System ROM 04/08/93 - ???
        AX = D823h
        BL = subfunction??? (00h or 80h)
        BH = ???
        DS:SI -> buffer for ??? (see below)
Return: CF clear if successful
            AH = 00h
            DH = 08h
            DL = ???
        CF set on error
            AH = error code
                86h BL neither 00h nor 80h
                87h ???

Format of buffer:
Offset  Size    Description
 00h    BYTE    ???
 01h    WORD    ???
 03h    BYTE    ???
 04h    WORD    ???
 06h    WORD    ???
        ???

.