Use this to exchange (Swap) Components, Gates and Pins of like devices either externally between different components using the same part, or internally between gates and pins in the same device to shorten the connection length between them. This should be run after component placement, and before routing the design.
The gate and pin swaps are recorded in the Back Annotation data used for updating the corresponding schematics design.
Auto Swap is only available if you have purchased the Pulsonix Autorouter/Autoplace option.
There are three Swap options:
- Auto Swap - the main option that considers all components in the design.
- Auto Swap Selected - available if some components are selected and only swaps between those selected components.
- Auto Swap Parameters - just changes the swap parameters. Used in a PCB technology file from the Setup menu to set up the correct swap parameters for later use.
Shortcuts
Default Keys: None
Default Menu: Tools
Command: Auto Swap All
Default Keys: None
Default Menu: Tools
Command: Auto Swap Selected
Default Keys: None
Default Menu: Tools
Command: Auto Swap Parameters
Locating this option
Available from: Tools menu > Auto Swap options
Prerequisites
Auto Swap requires that your PCB Design has components that have gate and pin swap group information in their parts. This swap data can only be added or changed in the part in the Parts library. See Parts Editor for details on how to set up Pin and Gate swap information.
When the part has been changed, use Reload From Library to update the components in your design.
How To Use Auto Swap
From the Tools menu, use the Auto Swap sub-menu option Swap All or Swap Selected.
The Auto Swap facility performs a number of passes of an iterative exchange of gates and/or pins in the same swap group, or swaps the positions of similar components. Use the switches in the following dialog to control this procedure.
Component Swaps
With this box selected, components using the same part can have their positions swapped so that the connection length is shorter. The netlist is not changed, and so component swaps do not need back annotating to the schematic.
Components are only considered for positional swap if they only have one gate in their part and it has a swap group greater than zero.
Gate Swaps
With this box selected gates can be swapped. Gates can be swapped with similar gates with the same swap group on the same component or with gates on other components using the same part. This depends on the Between Components check box.
When a gate is swapped with another, the connections ending on the corresponding pads are swapped. This changes the netlist and a gate swap is recorded into the back annotation data, ready for updating the associated Schematic design. The back annotation to the Schematic will not alter connections as it can simply swap the names of the gates in the design.
Between Components
Check this box to allow gate swaps between other similar components using the same part. Uncheck it if you want to restrict gate swaps to only between gates within each component.
Pin Swaps
With this box selected pins can be swapped with equivalent pins on the same gate and in the same swap group.
When a pin is swapped with another, the connections ending on the corresponding pads are swapped. This changes the netlist and a pin swap is recorded into the back annotation data, ready for updating the associated Schematic design. The back annotation to the Schematic will not alter connections as it can simply swap the names of the pins in the design.
On some designs you get better results by switching off pin swapping until all gate swapping has been performed and then run it as a separate procedure with just pin swapping selected.
Passes
This determines the number of tries Auto Swap will make in attempting to reach a minimum unrouted connection length of the overall design.
The higher the number of passes the Swapping option is allowed to make the higher the possibilities of lowering the overall connection length. There will be a finite number on any design where the number of passes cannot reduce the connection length any further. Experience with your type of designs will help you gauge the number required to get the optimum results. We suggest to try 4 passes initially and increase the number at increments of 1 until an optimum result is obtained.
Auto Swap
Press this button to start the swapping passes, or press Close to exit the dialog without swapping and save the swap parameters into the design. If swapping the following progress dialog will be displayed.
This has two progress bars. The top bar shows which pass you are on, and the bottom bar shows the progress within the current pass. The number of swaps performed so far is displayed above the second bar and the current part being swapped will be displayed in the title bar.
Press the Cancel button at any time to stop the swapping process. You will be presented with a message stating that swapping was interrupted, and asking if you want to keep the swaps performed so far.
If you let the swap progress complete, a dialog will be displayed showing how many swaps were performed and what the reduction in connection length is . If swaps were carried out, back annotation data will be saved into the design ready for applying to the associated schematic using the Back Annotation or Synchronise Designs options.
The Back Annotation data can be viewed using the Back Annotation Report.
What Will Not Be Swapped?
Locked Components
If the design contains locked components, you will be asked before entering the dialog what you wish to do with them. You can choose to ignore them, unlock them or swap within locked component. Components that are ignored will not be swapped and will not have any gates or pins within them swapped.
Pads with Tracks Attached
Pads that have tracks attached will not be pin swapped and their gate will not be gate swapped, and their component will not have its position swapped.
Components that are Not Similar
Two components using the same part will only be swapped if they have common attributes values and their ungated pins are on the same nets.
Saved in Technology
The parameters defined in this dialog are saved to both the design and as part of the technology. As such, they can be exported using Save Technology and loaded into new designs as part of a Technology file.
Related Topics
Technology Overview | Save Technology | Auto Place | Back Annotation | Back Annotation Report | Manual Swap Gates | Manual Swap Pins | Parts Library - Swap Information | Reload From Library | Synchronise Designs