DRC Custom rules

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Hello everybody!
I am trying to figure out why the custom rule I wrote, is not working when running DRC from PCB_Editor.
Running from kicad-cli it does not work either.

I have a board with two connectors (TPH): ETH1 on TOP and Euro/VME Connector on BOT. The Euro Connector does not have any Net or signal connected hence, it is only for secure the board to its backplane (it’s only mechanical).

The Ethernet RJ45 MagJack is connected. But due to space constraints some pins need to be removed from the Euro/VME Connector, so those pins are simply holes in the footprint with no connections at all.

Running the DRC it gives me this warning:

** Found 1 DRC violations **
[solder_mask_bridge]: Rear solder mask aperture bridges items with different nets
Rule: board setup solder mask min width; warning
@(150.6321 mm, 78.4726 mm): NPTH pad of X1
@(151.0861 mm, 79.7406 mm): PTH pad 12 [Net-(ETH1-Pad12)] of ETH1

I would like to exclude this warnig from the DRC check, so I can finish my project.

How write a custom rule for exclude this ?

Regards,
Gianluca

bug
bug705×578 37.8 KB

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Are you very sure you really want to do this? PTH and NPTH are made in different steps in the production process, and thus there are always alignment tolerances. Your holes look like they are quite close together, and as a result this may lead to production problems (I.e one hole overlapping the other due to alignment issues).

One way to reduce alignment tolerances is to define both of these holes as PTH pads. If you give them the same pad number, then KiCad also does not complain about overlapping pads, they are just merged into a bigger pad.

You can always exclude specific DRC violations right in the DRC window itself. Just right click on any violation and then exclude it. A quite new feature of KiCad is that each exclusion can be accompanied with a text comment of why the violation is excluded. This is mainly intended for the next developer (5 years after you left the company) and who then has to do maintenance on the project. But I’m not sure whether this feature was added to KiCad V9, or is only in the nightly at the moment.

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