blc(7)                                                        blc(7)


       NAME
             blc - BusLogic SCSI host adapter subsystem

       DESCRIPTION
             The BusLogic SCSI host adapter driver provides a Portable
             Device Interface (PDI) compliant interface to BusLogic SCSI
             Host Adapters.  The supported devices include the BT-747S and
             BT-946C.

             The BusLogic SCSI host adapter driver enables PDI compliant
             target drivers (such as sd01, st01, and so on) to communicate
             on the SCSI bus with target controllers and logical units.
             This allows normal access to mass-storage devices using
             standard system interfaces and filesystems.

             It is also possible for a knowledgeable user to access the
             SCSI-bus subsystem directly by using the driver's pass-through
             interface.  This allows the user to issue sb control blocks
             directly to a SCSI target device.  To find the appropriate
             pass-through device to use for a particular target device, the
             user should open(2) the character special file for the device
             in question and then issue the B_GETDEV ioctl.  The device
             value returned should then be used to create a character
             special file which, when opened, may be used for pass-through
             (SDI_SEND ioctl).

          ioctl Calls
             The following ioctl(2) commands are provided by this driver:

             SDI_SEND
                   Sends a pass-through command (SCSI control block) to a
                   target controller, bypassing the associated target
                   driver.

             SDI_BRESET
                   Resets the SCSI bus.

             B_GETTYPE
                   Returns the bus name (SCSI) and device driver name of a
                   specific device.

             HA_VER
                   Returns a ver_no structure describing this driver.





                           Copyright 1994 Novell, Inc.               Page 1

      blc(7)                                                        blc(7)


         Files
            /usr/include/sys/blc.h
            /usr/include/sys/scsi.h
            /usr/include/sys/sdi.h
            /usr/include/sys/sdi_edt.h
            /usr/include/sys/sdi_comm.h
            /etc/conf/pack.d/blc/space.c

      REFERENCES
            adsa(7), adsc(7), adse(7), adss(7), blc(7), dcu(1M), dpt(7),
            ioctl(2), mcis(7), sc01(7), sd01(7), st01(7), sw01(7),
            wd7000(7)

      NOTICES
            When configured at I/O Port 330 (default), both the adsc(7)
            and blc driver will claim the board.  The user should enter
            the dcu(1M) and disable the appropriate driver during
            installation.

            Extreme caution should be exercised when using the pass-
            through interface.  It is possible to interfere with normal
            system I/O and cause hangs if pass-through is used to an
            active device.  Pass-through should only be used to a device
            that is otherwise quiescent.
























                          Copyright 1994 Novell, Inc.               Page 2