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Seadog's avatar
Seadog
Icon for Occasional Contributor rankOccasional Contributor
6 years ago

Fitter error due to 'get_combs' command in .sdc file

I am getting a fitter error caused by a 'get_combs' command in the .sdc file; the get_combs command is part of a create_generated_clock command: -source [get_combs {blah_blah_blah\ ...
sstrell's avatar
sstrell
Icon for Super Contributor rankSuper Contributor
6 years ago

I don't understand. Something in your design is generating this .sdc file? get_combs is not a valid collection. You say "any time Quartus/Timing Analyzer has occasion to write the .sdc file". Are you saying you're doing a "Write SDC" command in the timing analyzer to generate this or is it getting generated in some other way?

#iwork4intel

Seadog's avatar
Seadog
Icon for Occasional Contributor rankOccasional Contributor
6 years ago

As you probably know, if you use the TA GUI to create a timing constraint, you can then cue TA to write out the updated .sdc file. When TA writes to the .sdc file, it is overwriting the edits I made to eliminate the offending 'get_combs' command. Then I have to manually edit the .sdc file, or Quartus errors out again when I try to do a build.