Re: [casper] How does one go about emphasizing timing over placement?

[Randy McCullough]

Henry Chen wrote:

Hi Randy,

If you edit the fast_runtime.opt file in the XPS_*_base directory,
you can add the -timing option under the Map section.

Thanks,
Henry

Andrew Martens wrote:

Hi Randy

The options used in mapping, place and route etc are found in fast_runtime.opt in the etc folder in the XPS_IBOB_base folder containing the EDK project created by the CASPER toolflow. You will find a bunch of options that you can play with here. Save the changes and then re-run the EDK/ISE/Bitgen step to run the ISE tools with the new options. I found that the existing options were quite well optimised for timing. The Xilinx documentation will provide info on the options to play with.

Good luck
Andrew

2008/10/1 Randy McCullough <rmccu...@nrao.edu <mailto:rmccu...@nrao.edu>>

    All,

    When reviewing the timing report of a failed build, the "Timing
    Improvement Wizard"
    nearly always suggests emphasizing TIMING over PLACEMENT using the
    "-t" option.

    Has anyone tried this?  If so, just how did you go about invoking
    the "-t" option under
    the umbrella of the bee_xps environment?  Are there certain
    configuration files that can
    be modified to accomplish this?

    Thanks,

    Randy McCullough
    NRAO, Green Bank

Andrew & Henry,

Thanks for the insight!

We tried this on a relatively simple bee2 design and it worked out quite
nicely.  At this point, we now have two gigantic builds running to create
the "DSP Engines" for our new 4K channel GUPPi instrument using this
technique.  Hopefully, this approach will greatly reduce (or eliminate?)
the timing errors we seem to be plagued with...

Thanks!

Randy