constraints coverage

Once upon a time I saw a number that told me what percentage of my project was unconstrained. I can't seem to get TRCE (Xilinx ISE) to show me that number again. Can someone point me in the right direction?

--
Prepend a 'b' to email me. Thanks.
Reply to
Brannon King
Loading thread data ...

For the command line version of trce, it is the -u option

Philip Philip Freidin Fliptronics

Reply to
Philip Freidin

trce used to report % of paths covered at the bottom of the .twr report, but that seems to have disappeared between trce v5.x to v6.x. It was a misleading number anyway becasue it included paths that could not be constrained, so 100% was not possible. Maybe that's why they quit reporting it. But, as Philip said, the trce -u option will report your unconstrained paths.

Reply to
Robert Sefton

Your guess is correct. We stopped reporting the percentage of paths covered because it was inaccurate and making the number 100% accurate turns out to be a very run time inefficient operation. We're still looking for an acceptable run time solution...

Russ Panneton

Reply to
Russ Panneton

Is there a way to list the unconstrained paths?

The timing report with trace -u only lists the number of unconstrained paths and the maximum delay. I would like to see them to assert that I have not missed a vital path in my constraints.

Reply to
Lars Theodorsson

The timing analyzer has no way of knowing which paths are vital to you.

Use -u followed by a number, e.g., -u 100, and you'll get a report of that many unconstrained paths, sorted from longest to shortest.

Bob Perlman Cambrian Design Works

Reply to
Bob Perlman

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.