Comparescan User Guide

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The entire_design.rules file is a text file that contains a rule that compares all of the signals in any input design:

compare .

Therefore, when your comparescan command completes, your current working directory will contain the following additional files:

■entire_design.csd is a binary Comparescan error database.

■entire_design.rpt is a text version of the information in the Comparescan error messages database.

The entire_design.rpt file contains the following comparison information in text format:

■A list of the objects that were compared and the mismatch errors that occurred

■A list of the objects that could not be compared and the reason why each object could not be compared

■The number of objects that were compared

■The number of objects that matched

■The number of objects that did not match

■The total number of each kind of mismatch error and the line number in the rules file of the rule that resulted in each type of error

■A list of the mismatches that occurred and the simulation time at which each mismatch occurred

You can load both of your simulation results databases into Signalscan Waves, select all of the mismatched objects in both designs, organize the mismatches in the Waveform window, and then scroll to the mismatch times given in the text report. However, if you view the binary error database in the Comparescan GUI, you can do all of the above tasks automatically, as described below.

Viewing a Comparescan Error Database

At the operating system command prompt, enter:

comparescan entire_design.csd

This opens the Comparescan GUI and loads the error database that you created with the -save option in the previous step. As shown in Figure 3-1 on page 20, the error summary and individual errors are listed just as they are in the text report (entire_design.rpt), but

Comparescan User Guide

Comparescan Tutorial

in this case, you can click on an individual error to display the mismatch in the Signalscan

Waves window.

Figure 3-1 Comparescan Window Showing entire_design.csd

The first line of text in the Comparescan window is the Summary message. This message tells you how many signals were processed, how many of the processed signals matched, and how many of the processed signals did not match.

The Info messages give you information about the comparisons, such as the reason why a given comparison could not be performed, and provide a summary of the types of errors that were found.

The Error messages list compare errors such as missing objects. Detailed mismatch errors for each object are reported below the Info error summaries.

Comparescan User Guide

Comparescan Tutorial

Viewing Errors in Hierarchical Order

By default, detailed errors are displayed hierarchically, as shown in Figure 3-2 on page 22.

This example shows 67 absolute compare errors. (Thirty are in scope hello and 37 are in scope top.) The letter M that appears before each scope in the list indicates that these objects are modules.

To view the compare errors that occurred under scope hello:

1.Click on the scope name hello.

The list of signals and sub-scopes in scope hello that contain compare errors is displayed, as shown in Figure 3-2 on page 22. The number of compare errors for each signal or sub-scope appears to the left of its name.

You can see that the object named c1 is a module because of the M symbol next to its name. You can also see that the object named o1 is a signal or variable because of the waveform symbol next to its name.

Comparescan User Guide

Comparescan Tutorial

Figure 3-2 View Objects in a Subscope

2.Click on the signal o1.

The detail list of compare errors for this signal displays, as shown in Figure 3-3 on page 23. The golden simulation signal name is given, then the secondary simulation signal name, and then the time window in which the compare error occurred.