Design And Implementation Of Schematic Verifying Tool Based On EDIF

With the increasing scale of the electronic system,enterprises and scientific research institutions have accumulated a lot of design experience,but most of the DRC functions provided by EDA tools are unable to accomplish custom rules verifying.It is difficult to transform design experience accumulated into custom verifying function in EDA tools.Some enterprises and research institutions use the API provided by EDA tools to develop plug-ins to implement custom verifying function,which is severely restricted by EDA tools.Its operation efficiency is generally low,the system needs a lot of maintenance after upgrading or upgrading EDA tools.Concerning about the universality and efficiency of the verifying system,it is particularly necessary to develop a schematic verifying system which can run independently and compatible with various EDA tools.Different EDA tool vendors use different private formats to save schematics,even the schematic formats between different versions of the same vendor are different.It is impractical to develop different parsing modules for schematic with different formats.EDIF standard has gradually become the mainstream description format of schematics,which has been widely supported by EDA tools.This thesis focuses on a custom rule verifying system of schematics based on EDIF standard and Python script.Firstly,export the schematic that needs to be examined in EDIF format.Secondly,use flex and bison to build lexical analyzer and parser to extract the schematic elements in syntax and semantic processing period and save it into the general data structure.Thirdly,several kinds of extension functions are provided in the verifying system,which can search or match schematic elements,obtain the object attributes and generate verifying reports.The extension functions can be combined into customized verifying rules,which are described in Python script.Finally,Python interpreter is integrated in the system to execute scripts.Multi thread technology is used in the interpreter,which allow multiple scripts to be executed at the same time to improve efficiency of verifying.Besides,a rule debugging environment is also designed in the review system.When debugging complex scripts,engineers can use breakpoint and single step execution to develop rules quickly and effectively.The verifying system is finally running on server clusters.Engineers just need to upload EDIF schematic files and select rule scripts,the verifying system will verify the schematic according to chosen rules efficiently and accurately,which shortens the product development period and provides a "cloud verifying platform" for enterprises and scientific research institutions.