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AR# 32619

SPI-4.2 v9.1 - Static alignment core might not go into frame in VCS timing simulation


The SPI-4.2 Sink core using Static Alignment might fail to go into frame (i.e., SnkOof asserted indefinitely) during a timing-based simulation with Synopsys VCS.


To work around this problem, change the following DCM phase-shift in the UCF file: 


For Virtex-5 devices: 

INST "<top_instant_name>/U0/clk0/rdclk_dcm0" PHASE_SHIFT = 25; 


For Virtex-4 devices: 

INST "<top_instant_name>/U0/clk0/rdclk_dcm0" PHASE_SHIFT = 35; 


NOTE: The phase-shift setting provided with the SPI-4.2 core in the constraint file is only a place-holder and might not be approriate for hardware operation. For more information on Static Alignment, refer to the SPI-4.2 User Guide (UG153).


This is fixed in v9.2 of the Core released in 11.3


Revision History 

05/04/2009 - Initial Release

04/07/2010 - Added fixed version

AR# 32619
Date Created 05/04/2009
Last Updated 05/21/2014
Status Archive
Type General Article