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In the Allegro back-end layout products like Allegro® Package Designer Plus, it would be reasonable to assume that the most often used command is none other than show element (shortcut key F4). This command, runnable at nearly any time in the tool, provides you the ability to get information about any database object you can select.
But it is NOT the only option for obtaining information! If you aren’t using them, consider trying some of the faster, more customizable ways to see and query important details about design elements as you work.
Labels drawn directly on top of objects in the design provide constant real-time data points for you. With them, you can rely less on other visual cues to determine what net items are on or even how far a via (stack) spans through the cross-section.
Enable these options through the Setup – Design Parameters command, as shown above. One note, though – you will need to have OpenGL rendering enabled in your tool. This is supported by all major operating systems today, though, and by many remote desktop clients (VNC, Exceed, No Machine, and more). Don’t worry if you’re stuck – like many of us are – working from home recently. These aids are available to you just as if you were in the office sitting at your workstation.
Below, you’ll see the labels in action. I will always know that I’m looking at net VCC because of the dynamic text on the cline and bond finger. Beyond that, I can see at a glance that my via goes from layer 2 to layer 3. If you assign (up to three characters) layer IDs to the layers within the cross-section editor, the via spans will be more valuable. Instead of 2:3, it can show M1:M2 or M4:BOT. The choice rests with you.
For span labels, a color between the start and end implies a single via, while a hyphen indicates a via stack. Also helpful information, depending on your layer stack type and rules about the maximum span for stacked vias before an offset is required.
Color is one of those attributes that we all use for highlighting items. Green means go, red means stop (or, in IC package substrates, green often means ground and red means power, but hey!). That’s why the custom coloring inside of Allegro® Package Designer Plus is so versatile. Apply both colors and pattern fill to any number of objects in your design to allow you to locate them immediately in the drawing window.
You can choose from any of 192 custom colors for design objects, as well as 16 different patterns (17, if you include solid).
Often, a subset of these are used for the default colors for the cross-section layers and for other layer categories such as Manufacturing and Substrate Geometry. I would recommend avoiding these colors when assigning custom colors to nets or other object types, since you won’t be able to tell at a glance whether the item is on layer M2 or part of net ABC if both are assigned yellow.
When you have configured color assignments just the way you want them, save them out with the File – Export – Parameters command, above. This allows you to reuse this same palette and coloring rules in any design file. Your color preferences need not be a concern for your coworkers, who can have their own color parameters based on how they work.
The last of the big three tools at your disposal for show element alternatives is the most like show element itself: data tips. These are the same features you’re used to in any modern design canvas. When you hover your cursor over a valid object, a window pops up with information about it.
Unlike show element, where the format and contents are fixed (to allow consistency for all users running the tool), the data tips window is fully customizable by you, the user, in the Allegro tools. Because of this, you see less data, more concisely organized, and easier to locate what you are looking for at this moment in time.
From the Setup – Datatip Customization command, it is possible to add or remove dozens, even hundreds, of pieces of data to be displayed (Note: the more data you add to the data tip, the larger its window will be when displayed).
Below, we see the customization settings for the snapshot above are set up. Whenever a piece of data is unavailable or unassigned on the item being highlighted, that line item is simply removed. Therefore, in our example, there are only three lines – the Verilog port name is not assigned for this power pin.
If you add your own properties on objects, you can add these to the data tips text through the advanced tab. At the bottom, in the Specify Datatips Format section, you can drag and drop items to be on the same lines or different lines. Put the most relevant items near the top and the less frequently needed attributes near the bottom.
Custom data tips configurations are stored on a per-user basis in your pcbenv folder. So, what you want to see need not be what your colleague in the cubicle next to you needs. A routing expert and an SI engineer rarely have the same interests, after all.
There are a few user preferences governing the data tips behavior which are worth noting. Most specifically, datatips_delay and custom_datatip_remove_delay specify how long before the tip window appears on a hover over and the duration it remains on screen before disappearing again, respectively.
The other most notable one is datatips_fixedpos. Set this, and instead of the data tip appearing next to your cursor and the highlighted element, the window always appears at the bottom-left corner of the design canvas pane. Most people find the cursor-position to be most useful, but if you are using this strictly as a replacement for show element, having it in the fixed position may be helpful to avoid it being front-and-center while you work. Drift your eyes down to see it as needed.
If you use the three features above today, what would make them better for you? Maybe it’s something wild and crazy – like having a hyperlink on the editable fields (net name, comment property, etc) so that you could click and either (A) directly edit the value right in the data tip window or (B) open the property editor to modify the field; or it might to include color-coding information in the window, to indicate an object has waived DRCs, open connections, or suppressed pads.
Have an idea? We’d love to hear it. As much as we are huge users of the show element tool like everyone else, we’re very much open to making the tool simpler, faster, more intuitive to use!