Internal Error: Sub-system: ASMIO, File: /quartus/comp/asmio/asmio_oct.cpp, Line: 922

Description

Due to a problem in the Quartus® Prime Standard Edition Software version 18.1 and earlier, you may see this internal error at assembler stage due to incorrect termination settings.

Resolution

To work around this problem, review your termination settings in the assignment editor and set it to a legal value as per device data sheet.