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Altera_Forum
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9 years ago

How important are System Design Contraint (*.sdc) files?

How important really is the SDC file? How important is it to eliminate all unconstrained paths? Does it have to be ALL of them? (such as altera_reserved_tdi and altera_reserved_tms that seem to wor...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
9 years ago

Unconstrained JTAG I/O, ignore it.

Timing violations in your processing path or critical I/O (GigE PHY, external memory), fix it.

Usually the .sdc is what allows you to see problems through TimeQuest. Actually fixing the problems being flagged may require design changes. i.e. you can't fix the .sdc if your logic is unintentionally sampling data from the wrong clock.