OCP(1)                      CAO-VLSI Reference Manual                     OCP(1)

               - Standard Cell Placer

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

       Web :
       E-mail :

       ocp    [options] netlist outputname

       ocp is an automatic place tool for standard-cells.

       input net-list
       The netlist file describes the input net-list.
       ocp supports a hierarchical net-list. In this case the net-list is
       flattened by the placer according to the catalog file. The net-list
       format can be : structural VHDL, EDIF, or ALLIANCE internal format
       according to the environment variable MBK_IN_LO.

       output layout
       The file containing the placed block will have the name outputname. This
       name is not optionnal and must always be present. The output format is
       defined by the environment variable MBK_OUT_PH.

       Optional cells placement file
       -partial <NAME>
       A user defined pre-placement can be specified, thanks to a placement
       The optional placement file must be given by the user. It must have an
       extension that denotes the format defined by the environment variable

       Optional connectors placement
       The placement of connectors can be also specified.
       There are four ways to place connectors in a physical view :
       -partial <NAME> pre-placed connectors defined by the user can be provided
       through the pre-placement file. In that case, automatic connector
       placement is impossible.
       -c option will automatically place the connectors randomly. The auto
       placement will set connectors on each side of the abutment box.
       -ring option will automatically place the connectors for the  ring pad
       placement tool. The placement is random but only on the north and south
       side unless the -ioc <NAME> option is given, in which case the
       constraints given in the <NAME>.ioc file will be respected, but with
       layers suitable for ring.
       -ioc <NAME> option will place connectors as specified by the <NAME>.ioc
       given file.

       It is possible to force the free area of the physical view.
       The -margin <MARGIN> option allow to set The amount of free area added in
       percentage of the cells area.
       The resulting area will be equal to CELL_AREA * (1 + <MARGIN>).
       By default, the margin value is 0.2 (20%)
       -eqmargin option will distribute equitably the margin between cells. By
       default, the biggest possible number of 2-pitch tie cells is inserted.
       This is done to have the best well and bulk polarity.

       Number of rows
       -rows <NR> option forces the design to be placed in <NR> rows.
       The abutment box's width is automatically generated.
       This option won't be used if a defined placement file is given.

       Verbose mode
       -v set the verbose mode on

       -gnuplot option allow to generate automatically gnuplot files, for
       editing statistics

IOC format
       The IOC format is based on Cadence input-output connectors placement
       The description is composed of 5 possibles sections: TOP(), BOTTOM(),
       LEFT(), RIGHT(), and IGNORE()
       In each section except IGNORE(), there are placed IOs.
       In the IGNORE() section, the IOs are ignored by OCP.
       In every section, the IO syntax could be:
       for pin:       (IOPIN iopinName.0 );
       for space:     SPACE  value;
       The capital words are keywords. orientation is not required.
       The value is the space (number of pitches) between the IO above and the
       IO below it.
       TOP ( # IOs are ordered from left to right
          (IOPIN b(3).0 );
          (IOPIN cin.0 );
          (IOPIN ck.0 );
          (IOPIN cout.0 );
       BOTTOM ( # IOs are ordered from left to right
          (IOPIN i(3).0 );
          (IOPIN i(4).0 );
          (IOPIN i(5).0 );
          (IOPIN i(6).0 );

       IGNORE ( # IOs are ignored(not placed) by IO Placer

       ocp uses the environment variables MBK_VDD and MBK_VSS to know the name
       of the power signals vdd and vss.

       nero(1), MBK_IN_LO(1), MBK_IN_PH(1), MBK_OUT_PH(1), MBK_VDD(1),

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

ASIM/LIP6                      September 27, 2001                         OCP(1)