Critical Issue
Description
In the Quartus Prime software version 16.0 (Standard and Pro Editions), the Periodic OCT Recalibration feature is enabled automatically for DDR4 designs whenever possible. This feature is not compatible with the Driver Margining feature of the debug toolkit, which measures the timing margin for a memory interface using a traffic pattern generator.
Resolution
The workaround for this issue is to disable Periodic OCT Recalibration when generating the EMIF IP if the design is to be used with driver margining.
This problem will be fixed in a future version.