Applied Parameters: None
Summary
This command is used to interactively route the connections on your board. Routing is the process of connecting the nodes in each net by placing a series of track segments and vias to define a path from one node to the next. The Interactive Routing tool helps maximize routing efficiency and flexibility in an intuitive way, including following cursor path for laying route sections, pushing obstacles, and automatically following existing connections, all in accordance with applicable design rules.
The Interactive Routing tool gives you full control over routing behavior and is designed to be easy to use on-the-fly, using the cursor and the keyboard shortcuts so that all routing options are available when you need them - during the route.
Access
This command is accessed from the PCB Editor by choosing the Tools » Legacy Tools » Interactive Routing command, from the main menus.
Use
After launching the command, the cursor will change to a crosshair and you will enter track placement mode. Placement is made by performing the following sequence of actions:
- Click, or press Enter, to anchor the starting point for the first track segment. If you click to start placement on an existing object, the track will adopt the net name of that object.
- Move the cursor to define the track segment and click, or press Enter, to anchor the end point for this first segment, which is also the start point for the next connected segment.
- Continue to position the cursor and click, or press Enter, to anchor a series of vertex points that define the series of connected track segments.
- Right-click, or press Esc, to end the current series of connected track segments.
When you start interactive routing, the PCB Editor will not only let you start placing track objects, it will:
- Monitor cursor position and mouse-clicks, applying all applicable design rules.
- Follow your cursor path, minimizing the number of actions required to place sections of routing.
- Monitor the connectivity and update connection lines as soon as you finish a route.
- Supports routing-specific shortcuts, for example pressing the * key on the numeric keypad to push to the next signal layer, inserting a via in accordance with the routing via style design rule.
As you route, click to place the tracks up to the cursor then continue moving your cursor and so on. This is so that the software can accurately maintain the path you have chosen - if you go too far before committing the tracks, it is possible that portions of your path will be altered.
As you route the net, the standard conflict resolutions modes are available: Push Obstacles, Ignore obstacles, and Stop at First Obstacle. Use Shift+R to cycle through the modes.
The following basic keyboard shortcuts can be used at any time:
- Click or Enter - commits the routing up to the current cursor position and places the tracks.
- Right-click or Esc - terminates the current route. Any routing that has been committed before calling the termination is retained.
- Backspace - unwinds the last committed route back to its starting point. If any objects had been pushed through placing the last segment, they are moved back to their original positions. This feature is not available after using Auto-Complete.
- Press the * key on the numeric keypad to cycle through the available signal layers. Alternatively, use the Shift+Ctrl+Wheel Roll combination to move through the routing layers, each notch of the mouse wheel will move to the next (or previous) available signal layer.
Press Shift+F1 to display all of the available shortcuts for commands available to you while in interactive routing mode.
Placement Modes
While placing track segments there are 5 available corner modes, 4 of which also have corner direction sub-modes. During placement:
- Press Shift+Spacebar to cycle through the 5 available corner modes: 45 degree, 45 degree with arc, 90 degree, 90 degree with arc, and Any Angle.
- Press Spacebar to toggle between the two corner direction sub-modes.
- When in either of the arc corner modes, hold the or keys to shrink or grow the arc. Hold the Shift key as you press to accelerate arc resizing.
- Press the 1 shortcut key to toggle between placing 1 segment per click (the first 5 images just below), or 2 segments per click (the last image in the set just below). In the first mode the hollow track segment is referred to as the look-ahead segment.
- Press the Backspace key to remove the last vertex.
Press Shift+Spacebar to cycle through the 5 available corner modes, press Spacebar to toggle the corner direction, press the 1 shortcut to
toggle placement between 1 segment or 2 segments.
Loop Removal
Altium Designer provides support for Loop Removal when interactively routing your nets. As you route there will be many instances where you need to change some of the existing routing. Rather than attempting to change the existing routing using a drafting type approach of clicking and dragging track segments, you re-route. To do this, launch the Interactive Routing command, click on the existing routing to start, and then route the new path, coming back to meet the existing routing. This will create a loop with the old path and the new path - no need to worry though, as soon as you right-click or press Esc to terminate the route, the redundant segments are automatically removed, including any redundant vias.
Tips
- Tracks on a PCB are made from a series of straight segments. Each time there is a change of direction, a new track segment begins. Also, by default, the PCB editor constrains tracks to a vertical, horizontal or 45° orientation, allowing you to easily produce professional results. This behavior can be customized to suit your needs.
- Interactive routing preferences are defined on the PCB Editor - Interactive Routing page of the Preferences dialog. These preferences can be accessed while routing by using the Tab shortcut.
- For a high-level overview on interactively routing nets in Altium Designer, see Interactive Routing.