Browse Prior Art Database

Graphical Query System

IP.com Disclosure Number: IPCOM000106584D
Original Publication Date: 1993-Nov-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 2 page(s) / 87K

Publishing Venue

IBM

Related People

Munger, GJ: AUTHOR

Abstract

Sometimes a chip designer will want to know: do I have an inverter connected to an inverter? Or there may be a replacement operation: find an NOR connected to a NOT, and replace them with an OR. This is not a global change NOR to OR, it requires examining the connectivity and perhaps other information. The query method can also be used in an exploratory fashion, complementing the interface provided by a browser/editor.

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Graphical Query System

      Sometimes a chip designer will want to know: do I have an
inverter connected to an inverter?  Or there may be a replacement
operation: find an NOR connected to a NOT, and replace them with an
OR.  This is not a global change NOR to OR, it requires examining the
connectivity and perhaps other information.  The query method can
also be used in an exploratory fashion, complementing the interface
provided by a browser/editor.

      Current tools used to modify an intermediate design are editors
and logic synthesis.  Editors have graphical interfaces that use the
net/line, block/box metaphor.  In general this interface is not
suited to making complex global changes.  With current technology it
has become hard to present global chip design data in a meaningful
way.  Logic synthesis systems are powerful but generally not
interactive.  Because the building blocks of a synthesis system are
compiled programs, synthesis is not well suited for "one shot"
problems.

      Graphical Query System (GQS) queries and modified VLSI design
data by specifying configurations.  This VLSI data consists of
connectivity information with attributes, such as block function or
power level.  Configurations are patterns of connected elements, with
partially filled in attributes.  For example, a simple configuration
might consist of an AND-function block connected to an
INVERTER-function.  There might be a large number of instances of
this configuration in a design.  Configurations are globally applied
by GQS against the data.

      The interface to GQS is entirely graphical, following the
traditional box and line representation for ECAD data.  Useful
configurations may be very complex.  A graphical notation was chosen
to make the tool's interface intuitive.

      The user if presented with an interface like that of a simple
schematic capture editor.  These are two drawing windows, one for the
query pattern and one for the replace pattern (if a modification is
desired).  Buttons select the type of object and window to activate
(query/replace).  Using the mouse, blocks and wires are drawn in the
appropriate window.  Connectivity in the pattern is determined by
placement.  Free wire ends are the i/o's to the pattern.  All the
circuits are represented by generic...