Device Family: Intel® Arria® 10

Type: Answers, Errata

Area: EMIF, Intellectual Property

Error Can Occur When Using Multiple EMIFs in a Single Column and Sharing RZQ Pins


If you are using multiple external memory interfaces in a single column, you might encounter the following error message when sharing RZQ pins:


Internal Error: Sub-system: AMM,

Fkile: /quartus/db/amm/amm_atom_mod_util_impl.cpp, Line: 4623

Cannot merge atoms - incompatible sources.


The workaround for this problem is to modify an RTL file deployed by the EMIF IP. Proceed as follows:

  1. Open all instances of the file
  2. Locate the instantiation of twentynm_termination_logic.
  3. Comment out or delete the line that connects the port s2pload of this module to the signal oct_s2pload.
  4. Recompile your design.

You should use a separate RZQ resistor for each external memory interface going forward, because doing so will improve the accuracy of calibrated termination settings.

This problem will be fixed in a future version.