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Altera_Forum
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10 years ago

Dose quartus use any Black magic to constrain dcfifo(gray code pointer)?

First of all, sorry for my poor English, I'm from China. The question is about gray code pointers in the async fifo. There are some similar post here: http://www.alteraforum.com/forum/sh...
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Altera_Forum
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10 years ago

Excellent! This is the proper way to do it. Xilinx's datapath_only is better than cutting the path altogether, but it doesn't account for clock skew between different bits of the gray code counter. Hopefully it's small, but shouldn't be ignored. Glad to see this being done right.

Does the user have to do this for the DCFIFO, or is it done already? Is the set_false_path embedded in the RTL still there, and if so how do they interact? Do you have an example?