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Last time, I talked about color and visibility as it relates to simplifying your design canvas display to make your work easier. Today, we take the next step forward: using your artwork films to drive what you see on screen, as well as dynamic text labels to help you find objects. We’ll close out with a reminder of how to recycle the time you’ve spent setting up one design across all your designs.
If you use artwork as your manufacturing format, you’re likely familiar with the ability, as you’re defining an artwork film record, to preview onscreen what will be included in the film. This display of the film isn’t limited to only the artwork setup command. As you define films, you may not have noticed a little, very helpful, item: the films appear in the color views pull-down in the Visibility tab:
In the View pulldown, located just below the global visibility buttons, you’ll find all your films listed by name. Selecting one will update your canvas visibility to match that film. This can be extremely useful as you move from one layer to another for routing-related tasks, but it also very useful when looking over your solder mask and silkscreen setups and other features.
You can define your own custom views (not associated with an artwork film) with the View menu commands, Color View Save and Net Visibility Manager. The first allows you to define a color view file on disk to set up global visibility, incremental changes, or to toggle the visibility of certain layers. The second lets you apply show/hide type rules, but this time for nets and ratsnest lines. As you build up your library of views, they will be available across all your designs.
Make use of the three types of views to quickly update the canvas to focus on what you are working on. Never do you lose the ability to manually control the visibility of specific layers; using views can help you turn a dozen clicks or more of your mouse into a single menu pick!
As a closing note for managing your visible layers in the active drawing, please don’t overlook the Enable layer select mode found at the bottom of the Visibility tab. This, which can be turned on or off any time, allows you to click on a layer’s name in the Visibility tab and the canvas will shift to only displaying that layer’s contents. Very helpful as you route through the layers!
If you have thousands of signal nets and a dozen different substrate layers, you’ll soon find yourself running out of unique colors to assign to everyone. That’s normal. Even if you have enough colors, if you’re anything like me, after the first dozen or so are assigned, it takes longer to remember which color belongs to which net. If I must think about it, that’s already more thought than should be needed.
Dynamic labels on elements supply you with the exact net name on objects. You can show them on clines, shapes, and/or pins. See the left side of the Design Parameter Editor form:
With these checks on, objects of the selected type that are assigned to a net will show the net name in the object. If you reassign an element’s net, the label immediately updates. These labels are invaluable as a mechanism to keep track of the nets you’re looking at when zoomed into a specific part of the design where context is harder to maintain. Don’t guess at whether you have the correct net. Know you do. There’s no need to waste precious seconds waiting for a tooltip to display and give you this information. Dynamic text labels are always there, ready for you to read when you need them. The only requirement? You need to be running with OpenGL graphics enabled. This is what allows the transparency and shading necessary for these labels to be ideally legible.
On the right side of the Design Parameters Editor form, you’ll find an option to show via span labels. In the following example, we can see the span for two different via elements. One from layer 11 to layer 12 and the other from layer 9 to 11.
Did you ever wonder why the top span has a colon (:) between the start and end layer, while the bottom uses a dash (–)? That subtle differentiation is important. A colon indicates a single via, while the dash denotes a stack of two or more vias.
As we close on discussing the tools that Allegro® layout editors provide to make your design easier to understand, one critical item remains: reuse. After spending the time to color your layers and nets the way you want them, would it not be wonderful to apply that SAME color palette to other designs that you work on? That consistency affords you less to remember, meaning more of your focus can be on the design work itself.
That brings us to the File - Import Parameters or File - Export Parameter commands. The export interface, shown in the following image, includes the sets of information which you can export. Saving out a parameter file will include this information in an easy to read XML format file that you can import into any other design whenever you want to apply the chosen colors.
The original design and target design don’t need to share the same layer names or net names. If a name referenced in your parameter file isn’t present in the target design, the entry is silently ignored. Meaning that if you have a few different naming conventions (or work with different teams, where each has a unique scheme), you can include all the names in one file. This makes applying your colors easier, needing only one file for any design.
With that, you should be all set! If our dive into these interfaces has left you with questions, or thoughts on functionality that would make your design tasks easier, please get in touch with the team. We’d love to hear about your experiences and suggestions!