Multi Pass Place and Route Mppr

Chapter 9: PAR

The last portion of the PAR report shows how many timing constraints were met and whether PAR was able to place and route the design successfully. The total time used to complete the PAR run is displayed in both REAL time and CPU time. Any errors and a message summary are also shown.

All constraints were met.

INFO:Timing:2761 - N/A entries in the Constraints list may indicate that the

constraint does not cover any paths or that it has no requested value. Generating Pad Report.

All signals are completely routed.

Total REAL time to PAR completion: 53 secs

Total CPU time to PAR completion: 11 secs

Peak Memory Usage: 99 MB

Placement: Completed - No errors found.

Routing: Completed - No errors found.

Timing: Completed - No errors found.

Number of error messages: 0

Number of warning messages: 2

Number of info messages: 0

Writing design to file c:\test\par0.ncd par done!

Multi Pass Place and Route (MPPR)

When running multiple iterations of the placer and router, PAR produces output design files for each iteration. When you run multiple iterations, you must specify a directory for PAR to place these files. PAR records a summary of all placement and routing iterations in one PAR file at the same level as the directory that you specify. Then PAR places the output design files, in NCD format, in the specified directory. For each NCD file, a PAR and PAD files (CSV, TXT, PAD) are also created, describing in detail each individual iteration.

Note: The naming convention for the output files, which may contain placement and routing information in varying degrees of completion, is:

[placer effort level]_[router effort level]_[cost table number]

The following is a command line example for running three iterations of the placer and router, using a different cost table entry each time.

par –n 3 -pl high -rl std address.ncd output.dir

–n 3 is the number of iterations you want to run,

–pl high sets the placement effort level to high

–rl std sets the router effort level

address.ncd is the input design file

output.dir is the name of the directory in which you want to place the results of the PAR run.

Note: Cost table 1, the default, is used for the initial cost table because no initial cost table was specified.

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Development System Reference Guide

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.

Xilinx 8.2i Multi Pass Place and Route Mppr, Par -n 3 -pl high -rl std address.ncd output.dir

Models: 8.2i