(Compare) 2: Individual Compare Signals

When comparing two waveforms, the signal names must match and one of the signals must be marked as compare in its Signal Properties dialog. When comparing two entire files, these options will be set automatically. However, if you are comparing individual signals, you will need to set these by hand.

Add a Signal and set its compare setting and change its name:

•Press the Add Signal button to add a signal to the diagram.

td1_sig_add_btn

•Double click on the name of the new signal (SIG0) to open its Signal Properties dialog.

•Change the name to Signal_To_Compare to exactly match the other signal in the diagram.

•Set the signal type to Compare.

•Notice that the name of the compare signal is blue.

singlelSignalComparison_addCompareSignal

Draw the waveform for the Compare Signal:

We will use the Waveform Equation generator to create a waveform that is similar to the one on the original signal.

•In the Signal Properties dialog of the compare signal, modify the expression in the Wfm Eqn so that it reads:

8ns=Z (3=1 7=0)*5 7=H 10=L 6=V 8=X

•Press the Wfm Eqn button to drawn the specified waveform.

SingleSignalComparison_wfmeq

singleSignalComparison_before_compare

Perform the Compare:

•Press the Compare button in either the dialog or on the button bar to calculate the comparison.

•Press the OK button to close the Signal Properties dialog.

•The red portions of the compare signal mark the areas where differences were detected. Also notice that the name is in red to indicate that there are differences somewhere on the signal.

compareButton_both_compares

singleSignalComparison_ZeroTolerance