Compiler Generated Junction

Parent page: Schematic Objects

The schematic compiler automatically adds junctions at each T-junction to complete the electrical connection.


A junction is an electrical design primitive. It is a small circular object used to join intersecting wires (or buses, or signal harnesses) on a schematic sheet. A Compiler generated junction is a junction that is automatically placed by the Auto-junctioning feature when two wires/buses/signal harnesses are connected in a T-type fashion, or when a wire/bus/signal harness connects orthogonally to a pin, power port or other electrical object. This auto-junctioning capability allows you to create electrical connections at junction points without needing to manually define the connections through the placement of manual junctions.


This type of junction is placed automatically by the Schematic Editor's Auto-junctioning feature. As such, it is not a design object that can be accessed and placed by the user.


Compiler generated junctions are placed automatically whenever a T-junction occurs during wiring, such as 2 wires/buses/signal harnesses meeting in a T, or a wire/bus/signal harness orthogonally crossing the end of a component pin or another electrical object, such as a Power Port.

If the Break Wires At Autojunctions option is enabled, on the Schematic - General page of the Preferences dialog, an existing wire/bus/signal harness segment will be broken into two at the point where an autojunction is inserted. For example, when making a T-Junction, the perpendicular wire/bus/signal harness segment will be broken into two segments, one each side of the junction. With this option disabled, the wire/bus/signal harness segment will remain unbroken at the junction.

Defining a Junction at a Cross Over

When one wire/bus/signal harness crosses directly over another, no connection is created (a compiler generated junction is not automatically placed). If a connection is required in this situation, a Manual Junction must be placed.

If a cross-over style junction is required, a manual junction must be placed.


A Compiler generated junction cannot be edited in the usual manner (via a dialog or graphically on the schematic sheet). The display properties of compiler generated junctions are configured on the Schematic - Compiler page of the Preferences dialog, as shown in the image below. Note that disabling the display of compiler generated junctions does not break the electrical connection at that junction point.

Configure the display options for compiler generated junctions (auto-junctions) in the Preferences dialog.


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