Waveform Comparison Option

Waveform comparisons graphically display the differences between individual waveforms or entire timing diagrams. This feature is exceptionally useful when comparing two different simulation runs, as well as for comparing logic analyzer data to a simulation run. A range of tolerances can be specified by the user from the compare signal settings to filter out insignificant differences. The Waveform Comparison feature may be added to any of our products.

To see how waveform comparison simplifies detecting differences, look at the two timing diagrams below.

How do they compare with each other?

Now look at the diagram window below, after using the compare feature:

Differences are indicated in red.

Also, the Report window shows differences in a time ordered list.

Finding and Selecting Differences

The compare icons make udating and setting tolerances easy and allows for quick selection of any difference in the diagrams.

Updates the timing diagram with current tolerance settings.

Selects the first difference and orients the timing diagram to it.

Finds the next difference and orients the timing diagram to it.

Finds the previous difference and orients the timing diagram to it.

Simultaneously selects all compare signals so that tolerances levels may be set.

Comparing diagrams using Tolerance

In the compare signal, the tolerance level can be set to ignore small changes. In the following picture, differences greater than 20 ns will be flagged.

A blue signal name indicates that the compare signal meets all tolerances. A red signal name indicates that the compare signal has differences greater thatn the tolerance settings.

Comparing Diagrams using Clock Signals

The diagram above demonstrates a "clocked comparison" where the compare is performed only on the negative edge of Clock. The only flagged signal is Global_Reset, which is indicated by the red name. Notice the two red differences on the high state.

Using the Compare feature in Batch Mode

The comparison feature can also be used in a batch .execution mode.