Placing two EMIF (External Memory Interface) IP cores on the same column in Arria® 10 results in a Fitter Error.

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Error (14566): The Fitter cannot place 1 periphery component(s) due to conflicts with existing constraints (1 IO_AUX(s)).

Please check the following two points

(1) If you have two EMIF example designs on the same column and you want to use the EMIF debug toolkit for each of them, you need to make them daisy chain. 
Please refer to the following user's guide and set the EMIF debug toolkit to be a busy chain.

（External Memory Interfaces Arria® 10 FPGA IP User Guide 
https://docs.altera.com/r/5ybDUDNrbPzSEVSGXW2L4g/vZUPLXWQ0TOVT6xMjtH76A
(see 14.7.1.4. Configuring Your EMIF IP for Use with the Debug Toolkit)

(2) The reset input of the two EMIF cores must be common. 
(External Memory Interfaces Arria® 10 FPGA IP User Guide excerpt) 
Multiple Interfaces in the Same I/O Column 
To place multiple interfaces in the same I/O column, you must ensure that the global reset signals (global_reset_n) for each individual interface all come from the same input pin or signal. 
https://docs.altera.com/r/5ybDUDNrbPzSEVSGXW2L4g/XerBZkdNfdb6aMW8Akyj7Q  
(search for Multiple Interfaces in the Same I/O Column)

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Category: External Memory Interface 
Tools: Quartus® Prime 
Devices: Arria® 10