Intel® Quartus® Prime Software
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TimeQuest command precedence for clock group

Altera_Forum
Honored Contributor II
1,174 Views

Hi Forum. 

 

In my system I got several clock domains and it is quite handy to set clock groups instead of false commands on thousands of paths. However it is not clear what happens to those ip fifo automatically generated sdc commands for crossing clock domains such as max delay or max skew. If they are then ignored then set clock groups is misleading and useless in my system.  

 

Any thoughts especially from Timequest gurus. Thanks in advance.
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Altera_Forum
Honored Contributor II
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If possible try to avoid clock group constraint applied to the clock that used by any IP, you wouldn't know it may cut those crucial paths without any explicit warning, like dcfifo in your example. It's better to verify each of path and false-path it through wildcard *

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Altera_Forum
Honored Contributor II
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Yeah, you can't use set_clock_groups if some of the cross-domain paths require analysis while others don't.

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