Community
cancel
Showing results for 
Search instead for 
Did you mean: 
AGoge
Beginner
918 Views

How can I make the least skew between data_in port and all registers it feeds?

I have to get the least skew between 1bit data_in port and all registers it feeds. I've tried to include "set_max_skew" to the SDC file but everything became even worse. In case when I used single receiver channel satisfying result was reached by option "lock region", but using this way to make good skew for 24 channels doesn't seem possible.

0 Kudos
2 Replies
28 Views

Hi,

 

set_max_skew is the constraint to specify maximum allowable skew between paths.

Did you compared the skew before and after the constrain in Timing Analyzer using "Report Max Skew" ?

https://www.intel.sg/content/dam/www/programmable/us/en/pdfs/literature/ug/ug-qpp-timing-analyzer.pd...

Page 65

Topic: 2.2.7.2. Maximum Skew (set_max_skew)

 

 

Another thing you might want to try remove the location constraint for the Input pins to give fitter more flexibility to achieve better skew.

 

Thanks,

Arslan

AGoge
Beginner
28 Views

Thanks for your reply.

I checked the skew by using a comand "report path" and my calculating the differece. I know that constrain skew is achieveble, but when I use "set_max_skew" the result of actual skew is worse than without any constrains. Here I have a small experement with this thing https://drive.google.com/open?id=1XC4QK_nwmswpdUEPY9IS4_woeTTtOxiL . Screenshots and some additional info in PDF and some instructions in readme.txt file. Also there's the project in this folder.

 

Reply