Routing - Routing Layers

Now reading version 3.0. For the latest, read: Routing - Routing Layers for version 4

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Rule category: Routing

Rule classification: Unary


This rules specifies which layers are allowed to be used for routing.

All design rules are created and managed within the PCB Rules and Constraints Editor dialog. For a high-level view of working with the design rules system, see Defining, Scoping & Managing PCB Design Rules.


Default constraints for the Routing Layers rule.Default constraints for the Routing Layers rule.

  • Enabled Layers - each of the signal layers currently defined for the design, as defined by the layer stackup, are listed. Use the associated Allow Routing option to enable/disable routing on a layer, as required.

How Duplicate Rule Contentions are Resolved

All rules are resolved by the priority setting. The system goes through the rules from highest to lowest priority and picks the first one whose scope expression matches the object(s) being checked.

Rule Application

Online DRC, Batch DRC, during interactive routing, and while autorouting.


When using the Autorouter, the routing direction for each enabled signal layer in the design is defined as part of the Situs Autorouter setup. Directions are specified in the Layer Directions dialog, accessed by clicking the Edit Layer Directions button in the Situs Routing Strategies dialog.

Setting the routing direction for a layer to Any can affect performance when autorouting. More efficient use of board area may be achieved by choosing a specific routing direction.
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