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Altera_Forum
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20 years ago

Highest CPU-Frequency for Cyclone I

Good morning. I`m new in this forum. I hope u will be able to answer my questions. The first should be rather trivial. What is the highest frequncy clock for a cyclone I? In my a...
Altera_Forum's avatar
Altera_Forum
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20 years ago

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originally posted by jesse@Mar 7 2006, 06:27 PM

the comments here are pretty accurate. there is one feature in sopc builder that can help. certain slave interfaces will slow things down substantially -- the tri-state bridge if many masters connect to it, and many slaves are driven by it, as an example. you could place this on its own clock domain (a separate, slower clock input will be generated from the sopc builder system that you must drive), and keep things like the cpu, sdram, and faster peripherals on the fast clock domain.

the clock crossing logic isn't the most optimal at the moment, though, so this approach makes sense only for peripherals you can live with slower access to (flash memory is a great example). also, the clock crossing generates additional logic for each clock domain crossing.. for this reason, its best to be selective with its use.. however, in these circumstances such as the above, it can help you maintain a significantly higher cpu frequency.

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So the SOPC Builder generates the clock crossing logic on its own? Thanks for the tip, I&#39;ll give this a try.