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Altera_Forum
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13 years ago

Source-Synch I/O Constraints

I've read just about every post by Rysc and Kaz on constraints. Many thanks for their contributions to this forum. I'm having trouble getting the constraints right for a source synchronous int...
Altera_Forum's avatar
Altera_Forum
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13 years ago

From the wording of the warning:

"no path exists between clock target mclk_p of clkA_ext and its clock source"

It looks like TQ is treating the muxed output mclk_p as if a register clocked by clkA_ext. Clearly it is not. Try set false path and see if it helps get rid of warning. I wouldn't worry otherwise.