Envisia HDL Modeling Reference

5

EDIF Interface

This chapter provides a brief overview of the EDIF (Electronic Data Interchange Format) interface capabilities within BuildGates synthesis. EDIF is an industry standard format for representing and exchanging such design information between various EDA tools. BuildGates synthesis supports EDIF 2.0.0.

Reading EDIF Designs

EDIF designs can be imported into the tool using the read_edif command:

ac_shell[1]> read_edif design.edif

yields the following output.

Info: Parsing of ’design.edif’ file succeeded <EDIF-700>.

Info: Netlist transformation of ’design.edif’ succeeded <EDIF-701>. Info: Setting ’TOP’ as the top of the design hierarchy <FNP-704>. Info: Setting ’TOP’ as the default top timing module <FNP-705>.

Since EDIF represents information in the form of structural netlists, there is no need to build the design using the do_build_generic command. The read_edif command parses the EDIF file and automatically populates the BuildGates synthesis netlist database. Thus, it is possible to execute any command after read_edif that is applicable to any module in the netlist, such as report_hierarchy, find or do_optimize. For example:

ac_shell[1]> read_edif design.edif ac_shell[2]> report_hierarchy

yields the following output.

|-TOP(g) ||-MIDDLE(g)

|||-BOTTOM(g)

ac_shell[3]>find -module -full

yields the following output.

Envisia HDL Modeling Reference

EDIF Interface

BOTTOM MIDDLE TOP

However, in case unresolved blackboxes remain after reading in EDIF designs, you may need to invoke do_build_generic to link such blackboxes.

Writing EDIF Designs

The write_edif command is used to write out designs in EDIF format. Assuming that the current module is TOP which has the following hierarchical structure:

ac_shell[4]> report_hierarchy

yields the following output.

|-TOP(g) ||-MIDDLE(g)

|||-BOTTOM(g)

The following command will write out an EDIF description of all the three modules: TOP,

MIDDLE, and BOTTOM

ac_shell[5]> write_edif -hierarchical out.edif

If the -hierarchical option is not specified, EDIF is only written out for the current module, in this case TOP:

ac_shell[6]> write_edif out.edif

The module MIDDLE will be represented as a blackbox in the EDIF output.