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Altera_Forum's avatar
Altera_Forum
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18 years ago

Having outputs changes behavior

Why would having outputs change the behavior of a circuit? I'm trying to test whats going on so I put in test outputs to read signals however the behavior of the circuit is different when I have the...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

My guess is you have a timing problem. It's not bringing the signals out that's causing the problem, it's the fact that you have a different fit and therefore different timing. That's usually what the problem is in those situations, and they're a pain to debug for that very reason(SignalTap and SignalProbe can be run on post-fit netlists, which is harder to work with, but allows you to get around this issue.)