Extending JMRI with rules in Logix - creating Junction Indicators (Feathers)

So far, we've built the signalling with the automatic rules within JMRI. But, sometimes it will be necessary to step outside the standard rules and make local adjustments.

In our layout, we have a Junction Indicator (Feather) to show the route is set into the Bay platform. At the time of writing, Junction Indicators have not been built into the JMRI signalling rules, so we need to define our own rules. We do this with Logix.

To begin, we need a Signal Head which controls the Feather. This is defined in the Signal Heads Table as a Single Aspect Signal, which can be "yellow" (or any colour offered!) or "dark".

Now we need to work out the rules which will cause the Feather to illuminate or go dark. Lets begin with "illuminate".

To illuminate the feather, the Down Approach Mast should be showing "Yellow" or "Off" (Calling On), and the turnout into the Bay platform should be thrown (route into Bay).

To turn off the feather, the Down Approach Mast should be showing "Red", or the turnout into the Bay platform should be "closed" (route into Platform 2).

Having outlined our rules in text, we can create two rules in the Logix Table. The video below shows the creation of the Feather Head and the Logix to control it.

Link to download the JMRI Panel File with the colour light signals completed below

[ Link to download 7 ]

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