Freerouter routing with a 4 layer board where inner layers are vcc and gnd

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Understand that in general, I should be doing manual routing but using freerouter has saved me quite a bit of time. My question is this. I create the inner layers with a zone tied to either GND or VCC as appropriate and the zone is 1mm smaller in all dimensions as the size of the PCB. I route a trace from one of the GND pins on the top layer to the blind via which goes to the GND layer. I have also done this for VCC. I then save, export to a dsn file, open it in freerouter and click autoroute. It appears to completely ignore that there is a GND and VCC layer and even the fact that I have created initial traces to those layers.

Is there something I am missing in freerouter or in pcbnew that is preventing the autorouter from creating blind vias to these power and ground layers?

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Interestingly, if I just make the 2 inner layers a trace layers and in freerouter choose horizontal and vertical for the inner layers under the parameter->autoroute menu item, it still ignores those inner layers when routing.

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I think that the original Freerouter only routes pairs of layers - see here


however there is also mentioned in the thread, a java version of Freerouter that will do 4 layers. https://freerouting.mihosoft.eu

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Are you sure that you want blind vias on a four layer board? They are expensive and only common on 6 or more layer boards with fine pitch BGA
I find that I use a ground plane layer and don’t bother with a VCC layer, most modern circuits use several supply voltages.
Th unbroken ground plane is the key to good EMC behaviour

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Thanks for the input. I’ll ditch the blind bias and check out the 4 layer free router

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A quick search shows that this is the only fork of Freerouting in active maintenance and supporting newer Java versions:

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Anyone with a github account want to contact him and see how committed he is to this? This might be a good place for them to be looking for help and advice. Maybe a sub forum devoted to it if there is enough interest? Problem is when I looked there seemed to be plenty of forks that were nothing more than updating to the latest version of Java and no real development.

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There is no real development there either. Just update to java11 and gradle, I checked it out.

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That alone is more than most Freerouting forks have done. The effort of running with newer Java is one of the reasons why the original developer dumped the project onto GitHub and walked away.
Java 8 is no longer supported by Oracle and is going away.
The Miho fork supports Java 9 in 1.3.0 and 11 in 1.4.0

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