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Altera_Forum
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18 years ago

"Hard routing constraints could not be satisfied"?

I recently made a small change to a design of mine and the fitter failed with an error I've never seen before: Error: Hard routing constraints for signal ddr_pll_cycloneii:pll|altpll:altpll_com...
Altera_Forum's avatar
Altera_Forum
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18 years ago

For the first example in Tristan's previous post, the -to field should be used instead of the -from field. Single-point assignments use the -to field even if the thing in that field is functioning like a "from". Quartus might allow the wrong field to be used if you edit the .qsf directly, but it will insist you use the "To" column if you use the Assignment Editor.

Regardless of the kind of assignment, for a single-point assignment use the "to" field regardless of whether the thing in the assignment is acting like a "from" or a "to".