R

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

Development System Reference Guide

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

Xilinx 8.2i is a significant version of the Xilinx ISE (Integrated Software Environment) that emerged in the early 2000s, marking an important milestone in the world of FPGA (Field-Programmable Gate Array) development. This version introduced a slew of advanced features, technologies, and characteristics that made it an indispensable tool for engineers and developers in designing, simulating, and implementing digital circuits.

One of the standout features of Xilinx 8.2i is its enhanced design entry capabilities. This version supports multiple design entry methods, including schematic entry, VHDL, and Verilog HDL, giving engineers the flexibility to choose their preferred approach. The integrated environment provides user-friendly graphical interfaces, making it accessible for both novice and experienced users.

Xilinx 8.2i's synthesis tools have been improved to enable more efficient design compilation and optimization. The new algorithms used in this version facilitate faster synthesis times while reducing power consumption and improving performance. Furthermore, it features support for advanced FPGA architectures, which allows for the implementation of more complex designs with greater efficiency.

The implementation tools in Xilinx 8.2i include advanced place and route capabilities, utilizing state-of-the-art algorithms for optimized resource usage. These tools enable designers to make better use of FPGA resources, ensuring that designs fit within the constraints of the target device while maximizing performance.

Another key characteristic of Xilinx 8.2i is its extensive support for various Xilinx devices such as the Spartan, Virtex, and CoolRunner series. This compatibility ensures that developers can leverage the powerful features of these FPGA families, including high-speed transceivers and DSP slices.

Xilinx 8.2i also places a strong emphasis on simulation and verification. The version integrates with various simulation tools, allowing for thorough testing of the designs before implementation. This reduces the risk of errors and ensures that the final product meets specifications.

In addition, this version includes support for design constraints, enabling engineers to specify timing, area, and other critical design parameters. By accommodating constraints, Xilinx 8.2i helps in achieving reliable and efficient designs tailored to project needs.

In summary, Xilinx 8.2i is a robust software development tool that enhances the design process for FPGAs. Its comprehensive features, including multiple design entry options, advanced synthesis and implementation tools, extensive device support, and strong simulation capabilities, make it a valuable resource for engineers and developers striving for innovation in digital design.
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