AST RESEARCH, INC.            TECHNICAL BULLETIN # 0963               8-24-94




                              ASCENTIA 900N PCMCIA USAGE


PROBLEM:        User is unable to use both PCMCIA slots without using the
                supplied Cardsoft drivers on the Ascentia 900N.

CAUSE:          Not using the Cardsoft utility provided with the system.

SYSTEMS
AFFECTED:           AST                                              REVISION
                PART NUMBER            DESCRIPTION                     LEVEL

                501299-2XX      ASCENTIA 900N 4/50 CS10                 All
                501300-3XX      ASCENTIA 900N 4/50 CT9                  All
                501302-2XX      ASCENTIA 900N 4/75 CS10                 All
                501304-3XX      ASCENTIA 900N 4/75 CT10                 All

SOLUTION:       If the user wishes to use both PCMCIA slots without using the
                supplied Cardsoft drivers on the Ascentia system, the user
                will be required to contact the vendor to get the independent
                "point enablers" to communicate with both PCMCIA slots.  If
                the user does not use the supplied Cardsoft drivers for the
                PCMCIA usage, the user will not be able to use both slots
                concurrently. the user will only be able to use slot "0".
                The following are technical details about the point enablers in
                slot 1 of the Ascentia 900N system.

                         Intel 82365SL PCMCIA controller
                                   __________
                                  |          |
                                  |          |------- slot 0
                                  |          |
                                  |          |------- slot 1
                                  |__________|

                This chip controls two slots using ports 3F0h and 3F1h. The
                access to control registers in each PCMCIA card is indexed
                through these ports.
                Slot 0 occupies indices 0 through 3Fh. Slot 1 occupies indices
                40h through 7Fh. The Ascentia 900N was implemented using this
                architecture.

                                   VLSI 82C146
                                   __________
                                  |          |
                                  |          |------- slot 0
                                  |          |
                                  |          |
                                  |__________|


                                   VLSI 82C146
                                   __________
                                  |          |
                                  |          |------- slot 1
                                  |          |
                                  |          |
                                  |__________|

                With the VLSI’s 82C146 PCMCIA controller, each chip controls
                one slot only.  There are two chips in the Ascentia 900N
                system to implement two slots.
                For slot 0, the control registers in the PCMCIA card are
                accessed the same way as the Intel slot 0 implementation.
                That is, through ports 3F0h and 3F1h with indices 0 through
                3Fh.  However, a PCMCIA card in slot 1 will be accessed
                through ports 3F4h and 3F5h with indices 0 through 3Fh.

                With socket services and card services installed, the VLSI
                implementation is supported properly because socket services
                communicates and understands the VLSI implementation.  But the
                point enablers that PCMCIA card vendors provide may not have
                been upgraded to support the VLSI implementation of slot 1.
                When this type of point enablers try to access slot 1 directly
                without socket service, they will not be able to access the
                card properly.
                A PCMCIA card running with such a point enabler in slot 0 will
                still function.