Internal Error: Sub-system: CUT, File: /quartus/db/cut/cut_atom_io.cpp, Line: 10493

Description

Due to a problem in the Intel® Quartus® Prime Pro Edition Software version 20.1, you may see this Internal Error when you connect the "pll_ref_clk" port of External Memory Interfaces Intel® Stratix® 10 FPGA IP to an unsupport clock source such as Clock Source BFM Intel® FPGA IP.

Resolution

To avoid this error, drive the "pll_ref_clk" from the external clock pin directly.