Xilinx 8.2i manual Initial Initial Budgeting of Modular Design, Initial budget.opt

Models: 8.2i

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XFLOW Flow Types

Table 23-8:Option Files for –implement Flow Type

Option Files

Description

 

 

weekend.opt

Multi-pass place and route (MPPR)

 

weekend mode

 

 

exhaustive.opt

Multi-pass place and route (MPPR)

 

exhaustive mode

 

 

The following example shows how to use the –implement flow type:

xflow -p xc2v250fg256-5 -implement balanced.opt testclk.edf

–initial (Initial Budgeting of Modular Design)

–initial budget.opt

Note: This flow type supports FPGA device families only.

This flow type runs the first phase of the Modular Design flow. In this “Initial Budgeting” phase, the team leader generates an NGO and NGD file for the top-level design. The team leader then sets up initial budgeting for the design. This includes assigning top-level timing constraints as well as location constraints for various resources, including each module.

This flow type invokes the fpga.flw flow file and runs NGDBuild to create an NGO and NGD file for the top-level design with all of the instantiated modules represented as unexpanded blocks. After running this flow type, assign constraints for your design using the Floorplanner and Constraints Editor tools.

Note: You cannot use the NGD file produced by this flow for mapping.

The working directory for this flow type should be the top-level design directory. You can either run the –initial flow type from the top-level design directory or use the –wd option to specify this directory. The input design file should be an EDIF netlist or an NGC netlist from XST. If you use an NGC file as your top-level design, be sure to specify the .ngc extension as part of your design name.

Xilinx provides the budget.opt option file for use with this flow type.

The following example shows how to run initial budgeting for a modular design with a top-level design named “top”:

xflow –p xc2v250fg256-5 –initial budget.opt top.edf

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Xilinx 8.2i manual Initial Initial Budgeting of Modular Design, Xflow Flow Types 8Option Files for -implement Flow Type