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AR# 53061

14.3 EDK, DDRx - "ERROR: tCK(avg) maximum violation by 33.335938 ps"


If I am simulating XPS Base System Builder designs containing the AXI DDR IP, tck error messages similar to the following occur on the simulator console:

"system_tb.inst_ddr_00.main: at time 76820837.0 ps ERROR: tCK(avg) maximum violation by 33.335938 ps"

How can I fix this?


This error occurs if the clock frequency driving the DDR3 device is lower than the DDR3 JEDEC specification value of 303 MHz:


In many of the Base System Builder projects, this will be set to 300 MHz, causing a mismatch that leads to tck errors.

This can be ignored in the simulation since the IP allows for this margin.

AR# 53061
Date 11/26/2012
Status Active
Type General Article
  • EDK - 14.3
  • EDK - 14.2
  • EDK - 14.1
  • AXI Spartan-6 FPGA DDRX Memory Controller