Step 2: Save Intermediate Synthesis Results

You can direct the Compiler to save synthesis results in a VQM File following compilation. The VQM File is an ATOM-based netlist that preserves the node names when the entity is exported and synthesized in another design.

To direct the Compiler to save intermediate synthesis results, follow these steps:

  1. Choose Settings (Assignments menu). The Settings dialog box appears.

  2. In the Category list, select Fitting under Compiler Settings. The Fitting page appears.

  3. Under Timing-driven compilation, make sure Optimize timing is turned on, and that Normal compilation is selected in the list.

  4. To avoid placing registers in I/O cells when optimizing a sub-entity, turn off Optimize I/O cell register placement for timing. Turning off this option ensures that sub-entity I/Os that do not exist in the top-level design are not exported.

    5. Show Me
    Fitting Page (Compiler Settings)

    Fitting Page (Compiler Settings)

  5. In the Category list, select Synthesis under Compiler Settings. The Synthesis page appears.

  6. Turn on Save a node-level netlist into a persistent source file.

  7. To save the filter.vqm file to the top-level project directory following compilation, type D:\qdesigns\logiclock\largefilter\filter.vqm in the File name box.

    8. Show Me
    Synthesis & Fitting Tab

    Synthesis & Fitting Tab

  8. Click OK to save the settings.


To continue the tutorial, proceed to Step 3: Specify Timing Requirements.