Easy way to find unrouted traces?

I was routing a semi dense board and got down to only one unconnected trace. I then spent the better part of 20 minutes looking for the last air wire.

In eagle someone had written a ULP that zoomed to first air wire it found. (called zoom unrouted)

Does something like that exist for KiCad or is there a good way to find unrouted traces?

And, I believe it will park a big red arrow at the physical location where it thinks the discontinuity is.

The cases that get the upper hand on me are very short traces (such as between adjacent pins on an IC), and the places where I lay down a trace that almost-but-not-quite connects to another trace. The traces may even overlap, but not enough to be sensed as “connected” by the DRC.

Just thinking aloud . . . in either canvas, if you disable display of all layers (except, perhaps, Edge.Cuts), then disable rendering of all objects EXCEPT Ratsnest, the unrouted connections should be pretty obvious. The colors chosen for the OpenGL canvas leave something to be desired for visual contrast but the incomplete nets are there for the looking.

Dale

You can change the colors.
(middle click on the color selector)

While that is true, the ratsnest in my PCBnew is white and the background black… still only manages a ratsnest line 1 pixel wide of a middle-grey tone… :confused:

Yea it would be nice to be able to also specify the width of the ratsnets line.

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I had a chance to play with the DRC. Thanks, didn’t know to look there.

The DRC does not place a red arrow where the unconnected traces are. Instead there is a second tab next to the error tab called “unconnected”. This contains a list of all the unconnected traces. Double clicking on an item in the list closes the DRC and centers the cursor on one end of the air wire. One note is that it does not change the zoom level. You can zoom in really close to the board, then run the DRC and then double click on an unconnected trace. This makes finding little tiny unconnected traces nice and easy.

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If I ignore some of the “green” ERC arrows in schematics, I believe the traces won’t connect to the pads in pcb new (in case of open connections). But what about power flag arrows?

Again: Not sure if this is the right topic to ask this question in. (Notice the layout tag of the topic itself.)

But to answer your question:
Erc does a few checks not only if something is not connected. (Erc is not the only thing that helps you detect that something is not connected. There is also a small circle or square at the end of pins/wires/labels if they are not connected.)

The power flag stuff is needed because power input pins need to be connected to some power output. In most PCBs the supply comes via some connector. This means one either needs to design a special connector symbol that defines the pins as power output or use the power flag. (The first option does not work if you have a passive component in series to the supply. Example: Fuse, series inductance of a filter, …)

If you want to know more look in the erc dialog under options. There you can see what generates a fault/warning.