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Altera_Forum
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11 years ago

How do I synchronize gray code counts safely across asynchronous clock domains?

I have a design for a generic asynchronous FIFO that I have used for many years. In this FIFO, I use gray code counters for the read and write pointers to the core memory. These multi-bit pointers mu...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

Unfortunately, set_max_skew pays attention to the set_false_path. Because of the set_false_path, Timequest will say there is nothing to report in the "Report Max Skew Summary". The set_max_delay would be correct, but there is no way to say "datapath_only" and have it ignore the clock trees.