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multicycle path latency

revk
Beginner
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Can I use a multicycle path to simply add latency without reducing effective clock speed?  I want to run at  300 MHz between registers A and B.  But I've got a negative setup slack. 

It's streaming data, so I don't care about the latency between A and B, I only care that B gets new data on every clock.  Is that possible with a multicycle path or is that just for logic that runs every N clock cycles?

 
 
Advance thanks,
Karol.
 
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Kenny_Tan
Moderator
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Yes, you may use this method.


You can take a look this link on how to do it https://www.intel.com/content/www/us/en/programmable/quartushelp/13.0/mergedProjects/tafs/tafs/tcl_pkg_sdc_ver_1.5_cmd_set_multicycle_path.htm


After doing the above, you should be able to see the result in timing analyzer. Check the behavior if this is the one you want.


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revk
Beginner
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Sorry for the late response getting back to this.  I read the documentation sent and more besides, but it's not really answering my question.  All of the examples I've seen show a signal that's got a lower sampling rate.  I want to keep the sampling rate but introduce a delay.  Typically one would do that simply with an extra register, but my timing is failing using that method.  The signal is simply a transceiver output in my case and it fails timing between the transceiver and the first register that uses the signal.

 
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Kenny_Tan
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We do not receive any response from you to the previous answer that we have provided. Please post a response in 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 with your follow-up questions. 


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