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What's Good About Viewing Constraint Differences? See for Yourself in Allegro 16.6!

Comments(2)Filed under: PCB Layout and routing, PCB design, Allegro PCB Editor, Allegro, PCB Editor, PCB, Grzenia, Allegro 16.6, 16.6, constraint databases, comparing constraints, constraint difference, constraints, viewing constraint differences

Starting with the Allegro PCB Editor 16.6 release, we can compare two constraint databases and view the constraint differences. This provides an efficient opportunity for designers to determine the differences between 2 designs.

Read on for more details

Generate a Constraint Difference Report

1. Open the Constraint Manager.
2. Select File > Import >  Constraints.
3. The 'Import Constraints' dialog box is displayed. Select the 'Report Only' check-box.
4. Choose the .dcf file to compare.  This .dcf file is exported from a different database.
5. Click 'Open' to create the report.

The Constraint Difference Report is shown below:

In the same way you can also select File > Import >  Technology File and open a .tcf file to view the Technology Difference Report.

View a Constraint Difference Report

The report can be opened in a built-in report viewer. This viewer consists of a toolbar and view window.
Report Viewer Toolbar:


The table below describes the function of each tool button.
Tools                                        Function
Previous                                   Selection shows previous view of the report
Next                                        Selection shows next view of the report
Export report to HTML               Export the report as an HTML page
Print Preview                            Shows a printer-friendly view of the report
Close Window                          Closes the report viewer

Export Report as HTML

1. Select the 'Export report to HTML' button from the toolbar. The Export Report dialog box is displayed.
2. Browse the directory to save the report.
3. Provide a report folder. 'OK' button gets enabled. Select OK.

The HTML page of the report is generated. You can open the HTML report page in any browser.

Printing a Report

1. Select the 'Print Preview' button from the toolbar.  The printer view is displayed for review.

2. Choose 'Send to printer' for printing the report.

Representing Constraint Differences

The Constraint Difference Report viewer is a two-frame, tree-view based representation.

Navigation Mode

1. By Tree-view shows a summary of the selected node in the tree-view:

2. By following Links, shows a summary of an object when selecting the object name link
3. By previous and next show selections made forward and backward in the report selections


View Layers

There are three viewing modes:
1. Summary only (S) shows a description only with the number of changes

2. Differences only(D) shows Destination and Source constraints for each attribute. Unchanged layers are not shown.


3. All values(A) shows constraints at Destination and Source for all layers.


Please share your experiences using this new 16.6 capability.

Jerry “GenPart” Grzenia


By Pawandeep on April 11, 2013
Hi Jerry, I cant see the pictures.

By Jerry GenPart on April 12, 2013
Hi Pawandeep,
I've not heard about pictures not being displayed in the Bog posts. What browser are you using?
I can see the images in these browsers:
Internet Explorer 8
FireFox 20.0
Chrome Version 26.0.1410.64 m
Jerry G.

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