Intel® Quartus® Prime Software
Intel® Quartus® Prime Design Software, Design Entry, Synthesis, Simulation, Verification, Timing Analysis, System Design (Platform Designer, formerly Qsys)
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unconstarained path error

tpwls
Beginner
816 Views

Hello!

 

I was working on a lab code at school and encountered an error in the timequest timing analyze part.

 

At first, a negative slack error and an unconstrained path error occurred together, but I solved the negative slack error by creating an sdc file with the wizard.


However, I was unable to resolve the unconstrained path error and would like your help.


I still have a limited understanding of quartus, so your help would be greatly appreciated.

 

Thank you.

manualmanual

test benchtest benchsdcsdc

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sstrell
Honored Contributor III
712 Views

Your .sdc does not include I/O delay constraints (set_input_delay, set_output_delay) so I presume those are what the tool is saying are unconstrained since you don't mention this.  You may want to get familiar with timing analysis: https://www.intel.com/content/www/us/en/docs/programmable/683068/18-1/timing-analysis-basic-concepts.html

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TingJiangT_Intel
Employee
628 Views

Hi there, is there any updates on this issue?


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tpwls
Beginner
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I solved the problem by creating a manual.out.sdc file with input/output delay set to 0 using TimeQuest Timing Analyze.

 

However, 332043 Overwriting existing clock: error has been added. How should this be resolved?

image.pngimage.png

 

Thank you.

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sstrell
Honored Contributor III
593 Views

You now have two .sdc files?  Why?  Combine them.

And I/O delays should not be 0 in a .sdc.

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TingJiangT_Intel
Employee
526 Views

Hi there, please check if there has some conflict constraint on this first, or if the overwriting is a right sdc you can ignore the warning.

As the previous reply, you'd better combine this two sdc file to ensure there is no conflict.


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TingJiangT_Intel
Employee
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Hi there, I now transition this thread to community support. If you have a new question, Please login to ‘https://supporttickets.intel.com’, view details of the desire request, and post a feed/response within the next 15 days to allow me to continue to support you. After 15 days, this thread will be transitioned to community support. The community users will be able to help you on your follow-up questions.


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