Synthesizing .vhdl files
Brad Beckmann
University of Wisconsin, Madison
1/25/00
Preface
Well you might have heard that Mentor's vhdl synthesizing tool doesn't
work or is extremely buggy. From what I've been told that is true
about their old synthesizing tool, but it is not true with the new and
powerful LEONARDO SYNTHESIZER. In true corporate America fashion,
Mentor bought a company call Exemplar who developed a working vhdl synthesizer.
Now Mentor is equiped with at great synthesizer and VLSI designers are
fearing that they will be replaced soon.
Optimizing using Leonardo
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Invoke Leonardo by simply entering the line % leonardo Doesn't
that windows interface bring back some memories.
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Type : load_library /s/mentor/adk/technology/leonardo/ami05_typ
at the prompt.
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Select the Input Flowtab. Set the Working Directory
to the directory that contains ripple_adder.vhd. Set Open files
to ripple_adder.vhd. Click on the Read button. You should
not receive any warnings.
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Select the Report Flowtab. Here is where you can receive reports
on the estimated area of your design and the delays of signals. Since
this is just a tutorial, we won't create these reports, but these reports
will be useful when you create your project.
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Select the Output Flowtab. Here is where you output a bunch
of various files including a EDIF netlist. This netlist will be used
to create a EDDM database and schematic that will be used to generate layout.
Select the EDIF Format and make sure that the filename is specified
as .../hdl/ripple_adder.edf Hit the Write button.
The file ripple_adder.edf should now be located in your /hdl directory.
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Close Leonardo.
EDIF to EDDM Conversion
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Now that we have a edif netlist create for our schematic, we need to convert
it to a EDDM database that is used by the ic layout tool. This is
done "simply" by entering the line % edif2eddm ripple_adder.edf ripple_adder
You probably get a few errors to scroll across your screen. Pay no
attention to these and lets hope it works anyways.
Once we have our vhdl file synthesized, we can look at it's layout.
Go to the next
tutorial on IC.