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... I don't know how to compare the speed-grades. Today I have a Cyclone3 speedgrade 6, but how do I know if 8 is sufficient?
Can anyone recommend any articles onthe subject or how you are choosing?
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You create your HDL for an example design, and constrain it with TimeQuest.
You then use Quartus to place-and-route the design for various devices.
Your Quartus TimeQuest analysis will then determine whether your design meets timing.
Here's an example where I've done this for the PCIe IP core to determine what speed grades it works in:
http://www.alteraforum.com/forum/showthread.php?t=35678 Cheers,
Dave
Honored Contributor
