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AR# 61230

Aurora 8B10B v10.2/v10.2Rev1 - Ultrascale GTH - Some of the Aurora 8b10b core configurations are failing with slack timing violation


Aurora 8B10B Core example design implementations run on UltraScale devices can fail with a slack timing violation as below:

Critical Warning [Timing 38-282] The design failed to meet the timing requirements on user_clk_i clock. The issue is due to create clock constraint on user_clk_i in <component_name>_exdes.xdc.

This Answer record provides the required edits.


Remove the below create clock constraint on user_clk_i from  the file <component_name>_example/ <component_name>_example.srcs/constrs_1/imports/example_design/ <component_name>_exdes.xdc and re-run implementation.

create_clock -name user_clk_i -period <value>    [get_pins aurora_module_i/clock_module_i/user_clk_buf_i/O]

This issue will be fixed in the Aurora 8B10B core released with VIVADO 2014.3.

Revision History:

06/23/2014 - Initial Release

AR# 61230
Date Created 06/22/2014
Last Updated 06/23/2014
Status Active
Type General Article
  • Kintex UltraScale
  • Virtex UltraScale
  • Vivado Design Suite - 2014.2
  • Vivado Design Suite - 2014.1
  • Aurora 8B/10B