Routing Enhancements

Routing-Aware Move Component

While routing the board, it is not uncommon for the designer to need to adjust the location of a routed component to create space for new routing.

This release sees the introduction of a routing-aware move component feature. The feature is enabled via the Component Re-route checkbox, in the PCB Editor - Interactive Routing page of the Preferences dialog.

A key requirement of the new feature is to preserve fanouts and escape routing. To make it easy to work with the new routing-friendly move component feature, the Tab-to-extend-selection behavior has also been improved. Use this to easily add any existing fanout and escape routes to the component selection so that all of the selected objects can be moved as an integral unit.

During the move process, the following shortcuts can be used to invoke the specified actions:

• Component Re-route Mode (Shift+R) - toggles post-drop connectivity restoration. After the moving set has been released, the software will attempt to re-route the component(s) to reconnect any broken nets. Use the Shift+R shortcut to inhibit the re-route behavior (or disable the Component re-route option in Interactive Routing page of the Preferences dialog). Current Status displayed in the Heads Up display and on the Status bar.
• Change Component Selection (Shift+Tab) - while dragging, the set of objects being moved can still be changed. Press Shift+Tab to cycle through the following selection sets:
  • Components only, then
  • Components +Via Fanouts +Escapes +Interconnects, then
  • Initial selection set (if different from the previous two), then
  • Back to Components only.

• Display / Hide Connection Lines (N) - previously the N shortcut was used to toggle the display of the connection lines on/off. The N shortcut now cycles through three states: no connection lines, pad-to-pad connection lines, and route-to-route connection lines. The last mode indicates where the connection lines have been severed and will possibly be restored, after the selection being moved is released.
• Change Gloss Effort (Shift+Ctrl+G) - cycle through the available Routing Gloss Effort options, to control the amount of gloss applied during component re-routing.

To make the Move Component behavior routing-friendly, the software detects and fixes violations in both the moving routing and the pre-existing routing. The default handling of violations is to visualize them while moving and attempt to resolve them on drop. Violations are resolved by pushing the pre-existing routing. Violations that cannot be resolved are left.

Interactive Router Follow Mode

A common requirement during routing is to place a route so that it follows an existing shape or contour. The contour could be an obstacle, a cutout or the board edge, or an existing route.

Rather than requiring the designer to route "against" the contour using careful and accurate mouse movements and click actions to ensure the new route hugs the contour, in Follow mode the designer simply clicks to nominate the contour, then moves the cursor along the contour to define the route direction. In Follow mode, the interactive router will add track and arc segments so that the new route follows the contour, in compliance with applicable design rules. This feature is particularly useful when placing curved routes.

To use the feature:

• Launch interactive routing, click to pick a connection to route, and switch to the required corner style (Shift+Spacebar).
• To follow a contour, position the cursor over the required object and press Shift+F, the Interactive Router will detect the object under the cursor and switch to Follow Mode.
• Move the cursor in the required direction, the software will automatically place track and arc segments to follow the contour in that direction.
• Left-click to place the Follow segments and drop out of Follow mode.
• Complete the route as required.

Glossing of Pushed Routes

A common request for the interactive router is to improve the way that pushed tracks are re-shaped as they are pushed away from the route being placed. In earlier versions, pushing would tend to plow, pushing existing routes so they flowed tightly around the new route. This would often result in Z shapes or acute angles, in the pushed routes.

The improved behavior is achieved through the addition of a number of new heuristics to the push and gloss algorithms that give more intelligent reshaping of existing routing, with reduced jigs and steps in the routes being pushed.

Interactive Routing Improvements

A number of other improvements have been made to the interactive router, including:

• Loop Removal - press the Shift+D shortcut while routing to switch to allow loops mode. The interactive router will remain in this mode until toggled off (toggle feature only available during interactive routing). Existing loops will be retained if loop removal is re-enabled and a net containing loops continues to be re-routed.
• Junction smoothing - automatic corner reshaping during interactive routing to avoid acute angles
• Gloss selected - improved glossing of multiple selected nets by reducing total length and number of bends.
• Gloss control - use the Ctrl+Shift+G shortcuts to cycle through the gloss modes, the current mode shown in the Heads Up display and on the Status bar. Available modes now includes None. Gloss can also be temporarily inhibited during interactive routing while holding the Ctrl+Alt keys down.
• Differential Pair Zip up - strong pair zip-up behavior improves diff pair pad exit and entry.
• Routing in presence of rooms - improved rule compliance when the routing properties change at room boundaries.
• New commands and features during a layer change:
  • Ctrl+L shortcut to pop up a list of available layers, click to select the target layer.
  • 1 to 10 Numpad keys to switch immediately to that layer number
  • Display a Z-plane view of the via that will be used for this layer change in the Properties panel.