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Altera_Forum's avatar
Altera_Forum
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18 years ago

Cyclone II is not working correct???

Hello, I have written a small process, which should read a dmx-signal (seriell signal with special timings). THe whole thing is working realy good, but sometimes it makes things, which i hav...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

Without having looked into any details of your design I would ask:

are all inputs to you statemachine syncronized before entering? I.e. they should pass at least one DFF clocked at the same clock as the SM. If not, you may end up having metastable state FF's, which will manifest exactly what you see: Erratic performance now and then.

Second point is: Check for warnings in timing analyser.