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Altera_Forum's avatar
Altera_Forum
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14 years ago

Clock skew from using global and local routing

I'm chasing a number of hold and sometimes setup violations that stem from impractical amounts of clock skew. When I pull up a failing path in the technology viewer, I find that one of the flops is ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

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It's saying it can't promote to a global for certain destinations(and then lists 10 of them, although there are surely many more). There's something going on. Are you maybe reading in a .qxp file? Is there maybe an .rcf in the project(routing constraint file).

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No rcf. While there was a qxp because it was set to save the logiclock regions after each build, I turn the setting off, deleted the file and rebuilt with no real difference. The first message went away but the "non-global" message is still there and the same flops have their flops driven by data lines.