When running Layout, use the Layout Options dialog box to set your Layout options.
The I/O Bank Assigner runs automatically after you click OK in the Layout Options dialog box. The I/O Bank Assigner automatically assigns technologies to all I/O banks that have not been assigned a technology.
Select this option to run Timing-Driven Layout. The primary goal of timing-Driven layout is to meet timing constraints, with a secondary goal of producing high performance for the rest of the design. Timing-Driven Layout is more precise and typically results in higher performance.
Standard layout is selected when the Timing-Driven check box is cleared. Standard layout maximizes the average performance for all paths. Each part of a design is treated equally for performance optimization. Standard layout uses net weighting (or criticality) to influence the results. Delay constraints that have been set for a design during place-and-route are not considered, however a delay report based on delay constraints entered in Timer can still be generated for the design. This is helpful to determine if Timing-Driven Layout is required.
Select this option to run the placer during Layout. If you have not run Layout before, Run Place is selected by default. If your design has already been placed but not routed, this check box is not selected. You can also select the following incremental placement options.
Incrementally: Select to use previous placement data as the initial placement for the next placement run.
Lock Existing Placement (fix): Select to use and lock previous placement data for the next incremental placement run.
Use the Effort Level slider to increase the effort Layout uses to place and route your design. The range is 1 to 5 with a default of 3. A higher level of effort generally improves the quality of results, but runs longer.
Select to run the router during Layout. By default, it reflects the current Layout state. If you have not run Layout before, Run Route is selected. Run Route is also selectedif your previous Layout run completed with routing failures. If your design has been routed successfully, this box is cleared.
Incremental routing is available for Axcelerator devices. When activated, the option sets the previous routing information as the initial starting point. To use the incremental routing option in the script mode, see the Advanced Tcl Layout options for Axcelerator (in the Tcl Scripting section).
Select to run layout multiple times with different placement seeds. Multiple Pass Layout attempts to improve layout quality by selecting from a greater number of layout results. Click Configure to set your Multiple Pass Configuration.
Note: To run Multiple Passes, you must select both Run Place and Run Route.