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Viewing Synthesis Results (Foundation Express Only)

With the View Estimated Performance after Optimization box checked, the Express Constraints Editor opens after the optimization phase of synthesis with preliminary performance results. The delay values are based on wireload models and, therefore, must be considered preliminary. Consult the post-route timing reports for the most accurate delay information.

  1. Under the Clocks tab, examine the estimated delay value of the clock. Delays greater than the specification appear in red.

  2. Under the Paths tab, examine the estimated delays for the paths and subpath. Click the source or destination of a path to see the members of the path, and click a specific path to see the individual segments of that path.

    Figure 5.16 Estimated Timing Data Under Paths Tab

  3. Examine the Ports tab to see that all of the settings and delays have been assigned and met.

  4. Under the Modules tab, you can examine the elements used to synthesize this design. Click the box in the second row under Area and select Details. This section summarizes all the design elements used in the Stopwatch design that Express knows about.
    Since the Tenths module is a LogiBLOX component and has not been synthesized by Express, it is UNLINKED and no summary information is available.

    NOTE

    Black boxes (modules not read into the Express design environment) are always noted as UNLINKED in the Express reports. As long as the underlying netlist (.xnf, .ngo, .ngc or EDIF) for a black box exists in the project directory, the Implementation tools merge the netlist in during the Translate phase. Since the Tenths module was built using LogiBLOX called from the project, the tenths NGC file will be found.

  5. Click OK to complete the Synthesis phase.

At this point, an XNF file exists for the Stopwatch design. See the “In-Depth Tutorial - Functional Simulation” chapter to perform a post-synthesis simulation of this design or refer to the “In-Depth Tutorial - Design Implementation” chapter to place and route the design.

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