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Altera_Forum's avatar
Altera_Forum
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13 years ago

Question about Combinational Loop Warning

Hi guys, I got a Fit warning like below: Warning (335093): TimeQuest Timing Analyzer is analyzing 45 combinational loops as latches. This warning is not very self-explanatory. There's no farther det...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

The warning is quite clear: you have designed combinatorial logic which somehow feeds itself with its own outputs.

This usually leads to a latch-like behavior. If you are not fully aware of the involved timings, you could have unpredictable results, race conditions, unstable outputs. That's why TQ warns you.