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

Chapter 9: PAR

R

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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