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AR# 65732

MIG UltraScale DDR4/DDR3 - "Reading unwritten address" warnings seen in simulation


In simulation, the following warnings from the Micron model might be given, even if the testbench does not read from unwritten address locations:

# Model:WARNING: Reading unwritten address: C:0 BG:0 B:0 R:0 C:6 dm:0 @11524.401 ns


These warnings are caused by the MIG periodic reads and can be ignored.

To remove these warnings, you can modify your testbench to first perform a dummy write to address location '0', so that it does contain valid data for the periodic reads.

Revision History:

10/16/2015 - Initial Release

AR# 65732
Date Created 10/16/2015
Last Updated 10/23/2015
Status Active
Type General Article
  • Kintex UltraScale
  • Virtex UltraScale
  • MIG UltraScale