Creating a VCD file

There are two flows in ModelSim for creating a VCD file. One flow produces a four-state VCD file with variable changes in 0, 1, x, and z with no strength information; the other produces an extended VCD file with variable changes in all states and strength information and port driver data.

Both flows will also capture port driver changes unless filtered out with optional commandline arguments.

The commands shown below are documented in detail in the ModelSim Command Reference.

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