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AR# 8420

Synplify - How do I change the BUFG limit from 4 to 8 for a Spartan-XL design? (BUFGLS)


Keyword: Spartan-XL, Synplicity, clock, infer, global, buffer 




General Description: 

Synplify limits global buffer insertion to four. However, in some architecture (such as Spartan-XL), a design can use up to eight BUFGLS. How do I change BUFG limit from 4 to 8 for these architectures?


Set the following attribute in the .sdc file to increase the limit of BUFG insertion in Synplify: 


define_global_attribute xc_global buffers (8)

AR# 8420
Date Created 08/21/2007
Last Updated 05/14/2014
Status Archive
Type General Article