Error CMP408: DDR instance <instance_name1> and <instance_name2> must share the same CLR signal if they are to be combined in the same bi-directional I/O instance <instance_name>.

When building a bi-directional DDR I/O macro, the input and output DDR cores must share the same CLR signal.

Action

Make sure that the two DDR cores share the same CLR signal in your design.