* *emergency* is a simple input connected to a device that detects the transponders of nearby emergency vehicles.
* *light-0*, *light-1*, and *light-2* are simple outputs connected to go/no-go traffic signals for three different directions at a hexagonal intersection.
* Control of the *lights* should be sequenced as indicated in the verification tab, turning off all lights when an *emergency* vehicle is detected and restarting the sequence when it leaves transponder range.

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* The durations of the phases are set by the operator using dials that can be read as XBus inputs.