Internal Error: Sub-system: HDD, File: /quartus/h/hdb_if_json_sys.h, Line: 226 - Internal Error: Sub-system: HDD, File: /quartus/h/hdb_if_json_sys.h, Line: 226 Description Due to a problem in the Intel® Quartus® Prime Pro Edition Software version 19.1, you may see this error during the synthesis stage of compilation. Resolution To work around the problem, remove instance assignments that have "auto_fab_0|*" as in the target (-to) field from the QSF (and other scripts sourced by the QSF) file. This problem is fixed starting with the Intel® Quartus® Prime Pro Edition Software version 20.1. Custom Fields values: ['novalue'] Troubleshooting 1507506876 False ['novalue'] ['FPGA Dev Tools Quartus® Prime Software Pro'] 20.1 19.1 ['Stratix® 10 FPGAs and SoCs'] ['novalue'] ['novalue'] ['novalue']