Compare by Signal
Clicking Compare > Add > Compare by Signal in the Wave window opens the structure_browser window, where you can specify signals to be used in the comparison.
You can also set signal options by clicking the Options button, which opens the Add Signal Options dialog box.
- Add Signal Options
The Add Signal Options dialog allows you to select the Waveform Comparison method to be used - Clocked (Strobed) or Continuous - and to specify a when expression that must evaluate to "true" or 1 at the signal edge for the clock to become effective. A when expression can be built using "The GUI Expression Builder" , which is accessed by clicking the Builder button.
Clocked Comparison
If the Clocked Comparison method is chosen, you can select a clock from the drop-down history of past clock selections or click the Clocks button to add a new clock.
Clicking the Clocks button opens the Comparison Clocks dialog box where you can add, modify or delete signals.
The Add button opens the Add Clock dialog, where you can define a clock signal name, a delay signal offset, the signal upon which the clock will be based, and whether the compare strobe edge will be the rising or falling edge or both. You can also use "The GUI Expression Builder" to specify a when expression that must evaluate to "true" or 1 at the signal edge for the clock to become effective.
Clicking the Modify button in the Comparison Clocks dialog opens the Modify Clock dialog. This dialog provides the same functionality as the Add Clock dialog.
Continuous Comparison
With the Continuous Comparison method you can set leading and trailing edge tolerances. The leading edge tolerance specifies how much earlier the test signal edge may occur before the reference signal edge. The trailing edge tolerance specifies how much later the test signal edge may occur after the reference signal edge. The default value for both tolerances is zero. In addition, these tolerances may be specified differently for each signal compared.
With Continuous Comparison, you can also use "The GUI Expression Builder" to specify a when expression that must evaluate to "true" or 1 at the signal edge for the clock to become effective.
