11.1 Known Issue - Constraints Editor - The Global branch does not list clocks associated with BUFR components

AR#	29887	Search For Another Answer
Topic	SW-Constraints Editor
Last Updated	04/15/2009
Status	Active

Description

Keywords: period, global, setup, pad, clock

The Global constraint table does not list PERIOD constraints for BUFR nets (in Virtex-4 and Virtex-5 devices), but these BUFR nets have their Pad to Setup and Clock to Pad fields filled in with "N/A".

BUFRs are capable of driving I/OLOGIC FFs and I/OSERDES, so OFFSET IN/ OUT constraints should be allowed for these clocks.

Solution

To work around this issue, manually edit the UCF and add the PERIOD to the output net of the BUFR component.

This issue will be resolved in the next major release of the design tools.