Length matching single ended buses

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Hi - I’m very new to KiCAD and am working on a bus that requires length matching of 50 ohm single ended traces. I have been looking around and not finding much information.

I watched this video: KiCAD now with differential pair routing and trace length matching | olimex but the length matching shown there was a bit basic - it required manually setting a target length and trying to tune to that. But that page is 10 years old.

How to Route Differential Pairs in KiCad | Sierra Circuits is also helpful - and shows how to make custom design rules for length matching diff pairs.

But that doesn’t really help me. Let’s take RGMII for example - I’d ideally want a panel that showed me the length of the 6 signals in one direction (so TXD0, TXD1, TXD2, TXD3, TXCLK, and TXCTL) and let me try to match to the longest of those. In my experience I route all the signals as best as I can, find which is longest, do my best to shorten it, and then lengthen the others to match that longest one. The example shown in the video linked above had every signal getting lengthened to a semi arbitrarily chosen length which does not seem like a good method.

So what is the latest and greatest method to do this in KiCAD 9? And can I set a design rule to compare a group of signals (like one direction of the RGMII interface, as mentioned above).

Thank you!!

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I do not see the difference between the two methods you mention. But if you insist on shortening your longest track a bit, then you first set the "semi arbitrarily chosen length" to a little bit shorter as your longest track.

I did see a part of the video. The length matching part seems to be from 05:00 to 09:30 and the method has not changed much in KiCad in the last 10 years. Except maybe that now the meanders are placed in a “length tuning box” and you can change the size of that box later (or delete it). Maybe KiCad V9 has improved a bit further, but I’m still on V8.