The Differences panel is used to display all logical differences that have been found by the Comparator when comparing design documents (for example, comparing the source document hierarchy for a project against the PCB design document).
The panel allows you to explore the differences before deciding to create an ECO that will ultimately be used to synchronize your documents.
When graphically comparing the differences between two versions of the same schematic or PCB document, the panel will list the differences detected and allow you to display the differences simultaneously on the two documents open side by side in the design editor window.
Content and Use
The use of the panel depends on whether you are comparing different documents with a view to detecting logical differences, or whether you are comparing two versions of the same document with a view to detecting graphical differences (schematic and PCB documents only).
Displaying Logical Differences
Comparison of documents for logical differences is carried out using the Project » Show Differences command, which will open the Choose Documents To Compare dialog.
Typically you would compare the PCB document against the source document hierarchy for the parent project.
After clicking OK, if any differences exist between the nominated documents, the Differences between dialog will appear. Information in the Differences panel will only appear after pressing the Explore Differences button in the Differences between dialog.
The Differences panel can only display the differences that are listed in the Differences between dialog. These, in turn, are determined by the selections made in the Comparator tab of the Options for Project dialog. This tab lists all of the comparison types - differences associated with Components, Nets and Parameters - and depending on whether you have chosen to Find Differences or Ignore Differences for a particular category, the Comparator will either pass the results into the Differences between dialog or not.
The panel displays the differences found between documents in a tree-like structure. The top-level folder displays the total number of differences detected. Sub-folders are then created for each specific comparison type that appears in the Differences between dialog. In each sub-folder are listed the specific differences that have been found, which in turn are broken down further into objects on the compared documents that are responsible for the differences arising.
If the associated document is open (or open and hidden), clicking on an object entry in the panel will cross-probe to the object on the document. The visual display of the object is dependant on the Highlight Methods defined on the System - Navigation page of the Preferences dialog (DXP » Preferences). These options include zooming, selecting and masking, the latter of which causes all other objects on the document to become dimmed, leaving only the offending object fully visible.
Displaying Physical Differences
The comparison of two versions of the same schematic or PCB document can be carried out in the following three ways. In each case, any detected physical differences between the two documents will be listed in the Differences panel:
- Comparison can be performed using the Project » Show Physical Differences command. Ensure that the previous version (typically a backup) of the document is saved with a different name before opening. The backup version of the document does not need to be added to the project, it can be opened as a free document. Then, run the command to access the Choose Documents To Compare dialog which, when configured in Advanced mode, can be used to select the two versions of the document for comparison.
Clicking OK will proceed with the comparison and the detected differences will be displayed in the Differences panel
- Comparison can be performed from within the Storage Manager panel by selecting two versions of the document in the Local History region (or VCS Revisions region if your documents are under version control using CVS or SVN), right-clicking and choosing Compare. A graphical comparison is made and the detected differences listed in the Differences panel. With the two versions of the document open side by side in the design editor window, you can peruse the differences graphically. Clicking on a top-level folder for a detected difference will highlight that difference on both documents simultaneously.
- Comparison can be performed from the Local History dialog for the active document in the design editor window (accessed using the Project » Local History » Show Local History command). The dialog lists the current version of the document and any stored backups.
Select two versions of the document that you wish to compare and click the Compare button. A graphical comparison will be made and the results displayed in the Differences panel.
The panel displays the differences found between documents in a tree-like structure. The top-level folder displays the total number of differences detected. Entries are then created for each difference, with a corresponding icon to depict the design object involved in the difference (e.g. port, part, etc). Beneath these entries are the actual objects on the two compared documents.
Clicking on the entry for a detected difference will highlight the 'offending' object in both versions of the document simultaneously. Click on the sub-entry for an object to highlight it on its parent document separately.
- If an object in the panel resides on a document that is currently hidden, the document will be opened automatically and made the active document in the design editor window, when you click the associated entry.
- The extent of 'dimming' applied when the masking highlight option is enabled can be manually adjusted using the Dim slider bar - accessed by clicking the Mask Level button, to the immediate left of the Clear button, at the bottom-right of the design editor window.
- The filtering applied when cross-probing from the Differences panel is temporary. Clicking inside the design editor window will clear the filter. As such, you are not prevented from selecting or editing design objects that fall outside the scope of the filter.
- Clicking on an object associated with a difference in the Differences panel will display information specific to that object in the Compiled Object Debugger panel.
The information in the Differences panel will disappear when performing a new document comparison, or compiling the parent project.