s2r

S2R(1)                      ALLIANCE USER COMMANDS                      S2R(1)



NAME
       s2r    - Process mapping from symbolic layout to physical layout

SYNOPSIS
       s2r [-tc1rv] source [result]


ORIGIN
       This software belongs to the  ALLIANCE CAD SYSTEM developed by the ASIM
       team at LIP6 laboratory of Université Pierre et Marie CURIE, in Paris,
       France.

       Web : http://asim.lip6.fr/recherche/alliance/
       E-mail : alliance-users@asim.lip6.fr


DESCRIPTION
       The goal of s2r is to perform the translation from the symbolic layout
       to physical layout for the foundry.  s2r uses a technolgy file whose
       name is defined by the environnement variable RDS_TECHNO_NAME.
       Some cells, like I/O pads, are specific to a given foundry.  In the
       symbolic methodology, these cells are phantom cells.  It means that
       only their abutment box and and connectors are present.  s2r wil
       substitute physical cells to the symbolic phamtom cells.  Beware, this
       implies that the manufacturer cells must be modified by hand to ensure
       the abutment box is a symbolic grid step multiple, and that the real
       connectors are centered on symbolic grid.
       In order for the replacement to work well, the physicals cells must
       have the abutment box lower left corner at coordinate (0,0) The name of
       cells to be replaced are written in the catalog file with the G
       attribute, see catal(5) for details on that file.  See also ring(1) for
       more on pads.  Ouput can be generated in either cif or gds formats, to
       fit the manufacturer requirements.

       Mainly two kinds of users are concerned with s2r :

       experts              they should be able to parametrize the technology
                            file for a new process technology file is
                            described in techno(5).

       designers            they are not directly concerned with the target
                            process, but need to be able to compute real
                            capacitances for simulation.

       The source argument is the name of the symbolic layout file to be
       translated.  The optional result argument indicates the name to be
       given to the real layout output.  This name is also the name of the top
       level model of the layout hierarchy.  If result name is omitted, then
       source name is used.

       Six environment variables must be set for proper usage of s2r, all of
       them having default values, thus ensuring the possibility of using it
       ``as it is''.

       MBK_IN_PH            The input format for symbolic layout is given by
                            this environment variable.  The possible values
                            are  cp, ap. Default is cp.  See MBK_IN_PH(1) for
                            details.

       MBK_CATA_LIB         Sets the directories that are to be searched thru
                            for reading files.  The seaching mecanism first
                            look in MBK_WORK_LIB(1) MBK_WORK_LIB defines the
                            path where the generated file is saved.  Make sure
                            the write permissions are set up correctly,
                            otherwise no save will occur.

       MBK_CATAL_NAME       This indicates the name of the catalog file used
                            for pad substitution.  For the appropriate syntax
                            of this file, see catal(5).

       RDS_IN               Defines the format to be used as input for cell
                            substitution.  The available ones are cif and gds
                            (default one).  The cells to be parsed must not
                            containt 45 degrees wires. If an unknown layer is
                            encountered, the entire cell will be skipped.

       RDS_OUT              Gives the format of the output file.  This may be
                            either cif or gds (default is gds).

       RDS_TECHNO_NAME      This points to the technology file to be used for
                            symbolic to real translation.  This file is in
                            general shared between all the designers.  it is
                            the full path name to the file location, with the
                            extension.

OPTIONS
       Without option, s2r should produce a layout that fits for the foundry.
       Nevertheless, its behaviour can be modified when invoked with the
       following options:

       -t                   Suppress the denotching phase. s2r performs gap
                            filling, denotching in order to avoid DRC errors.
                            This operation is time consuming.  It is mandatory
                            for the foundry but not really useful for
                            capacitance evaluation.

       -c                   Deletes connectors and node names at all hierarchy
                            level.  Theses objects link the physical view and
                            the logical view of a chip.  If simulation is to
                            be done after physical mapping, connectors must
                            appear, so that the extractors and simulators can
                            use them.  This must not be used when preparing a
                            final layout for the foundry.
                            For the factory, the top level connectors are
                            forbidden, since they do not represent any
                            physical reality.

       -1                   Creates the top level cell with the instances as
                            black boxes.  This may be useful for hierarchical
                            extractors, since the file size may be greatly
                            reduced.

       -r                   does not replace black boxes.  Cells flagged with
                            the G attribute in the catal(5) file will not be
                            replaced by their equivalent layout loaded from
                            disk.

       -v                   verbose mode on.



EXAMPLES
              You should first have a correct execution environment :
              It is recommanded to put it in the ``.cshrc'' file if in c
              shell, as in the example below.

              setenv MBK_IN_PH       ap
              setenv MBK_WORK_LIB      ~fred/mbk/layout
              setenv MBK_CATA_LIB      ~franck/s2r:/alliance/cells
              setenv MBK_CATAL_NAME    catalog
              setenv RDS_TECHNO_NAME   /labo/etc/prol15.rds
              setenv RDS_IN            gds
              setenv RDS_OUT           gds
              s2r -c na2_y
              This invocation will produce the cell na2_y from the standard
              cell library in real layout, without connectors, scotches if
              needed, in gds format.

SEE ALSO
       mbk(1), ring(1), MBK_IN_PH(1), MBK_CATA_LIB(1), MBK_WORK_LIB(1),
       MBK_CATAL_NAME(1), RDS_IN(1), RDS_OUT(1), RDS_TECHNO_NAME(1),
       techno(5), catal(5).


DIAGNOSTICS
       The actual version of the gds parser and driver doesn't translate
       neither connectors, nor node names.  If an extraction on s2r output is
       needed, cif format will create the connectors using cif extension 4X,
       and the node names with 4N.





BUG REPORT
       This tool is under development at the ASIM department of the LIP6
       laboratory.
       We need your feedback to improve documentation and tools.






ASIM/LIP6                       October 1, 1997                         S2R(1)