Int 13 Fn 18  - Future Domain Scsi BIOS - Get Scsi Controller Information  [d]

   AH = 18h
   DL = hard drive ID

Return: CF set on error
       AH = status code (see AH=01h)
   CF clear if successful
       AX = 4321h (magic number)
       CX = controller family code (see below)
       ---if family code=0200h
       DH = number of exclusively ROM-controlled SCSI devices
       DL = canonical SCSI device number for specified drive
       ---if family code <> 0200h
       BH = number of exclusively ROM-controlled SCSI devices
       BL = canonical SCSI device number for specified drive

Notes: also sets an internal flag (non-resettable) which prevents some
     controller messages from being displayed, allows writes to
     removable devices (use caution!), and enables the INT 13 interface
     for more than one drive (i.e. DL >= 81h) in at least some ROM
     versions
   the TMC-950 does not support any Future Domain BIOS calls; instead,
     it provides a full CAM implementation (see INT 4F/AX=8100h)

See Also: AH=05h"SCSI",AX=1700h"SCSI",AH=1Bh"SCSI",INT 4F/AX=8100h

Values for controller family code:
 0200h TMC-1680/? (ROM 3.0)
 0203h TMC-1650/1660/1670/1680 (ROM 2.0)
 040Ah TMC-820/830/840/850/860/870/875/880/885 (ROM <= 6.0A)
 050Dh TMC-840/841/880/881 (ROM 5.2D)
 0700h TMC-830/850/860/875/885 (ROM 7.0)