adsc(7)                                                      adsc(7)


       NAME
             adsc - Adaptec Standard Mode SCSI host adapter subsystem

       DESCRIPTION
             The Adaptec Standard Mode host adapter driver provides a
             Portable Device Interface (PDI) compliant interface to any
             Adaptec Host Adapters that support the Adaptec standard mode
             interface.  These devices include: AHA-1540B/1542B, AHA-
             1540C/1542C, AHA-1540CF/1542CF, AHA-1640, AHA-1740/1742, AHA-
             1740A/1742A.  Note that the AHA-174x and AHA-174xA series are
             only supported by this driver when configured in standard
             mode.  Support for the AHA-174x and AHA-174xA when they are
             configured in Enhanced Mode is provided by the adse(7) driver.

             The Adaptec Standard Mode 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.



                           Copyright 1994 Novell, Inc.               Page 1

      adsc(7)                                                      adsc(7)


            HA_VER
                  Returns a ver_no structure describing this driver.

         Files
            /usr/include/sys/adsc.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/adsc/space.c

      REFERENCES
            adsa(7), adse(7), adss(7), dpt(7), ioctl(2), mcis(7), sc01(7),
            sd01(7), st01(7), sw01(7), wd7000(7)

      NOTICES
            Adaptec SCSI controllers cannot be used reliably with Emulex
            SCSI/ESDI bridge controllers (also known as AT&T DCM/4E).
            This is due to hardware induced timing differences between
            these bridge controllers and any SCSI controllers other than
            the one that they were designed to be used with.  It is not
            possible to provide a software solution to this problem.

            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