Quartus® Prime Pro Edition User Guide: Block-Based Design

ID 683247
Date 8/30/2025
Public
Document Table of Contents

3.4.3. Preserving I/Os (other than GPIO IP I/Os) in I/O Banks in Safety Partitions

You can add it to the .qsf or use Pin Planner.
  1. In the .qsf, indicate the I/O is preserved for safety designs with the .qsf instance assignment ENABLE_FUSA_PRESERVATION.
    set_instance_assignment -name ENABLE_FUSA_PRESERVATION <ON/OFF> -to <pin_name>
  2. Alternatively, in Pin Planner, in the column Strict Preservation set the assignment value of each listed I/O pins.
    Figure 33. Preserving I/Os in Pin Planner
    When the assignment value is ON, the Quartus® Prime Pro Edition software places the I/O in the same safety partition of the logic it connects. The software produces error messages:
    • If the logic the pin connects to is not in a safety partition.
    • If the pin connects to more than one safety partition.
    • If the pin connects to a mixture of safety and non-safety partitions.
    When the assignment value is OFF, the Quartus® Prime Pro Edition software:
    • Places the I/O at the top partition regardless of whether or not the logic it connects to is in safety partition.
    • Produces an error message if you instantiate the I/O manually in the safety partition.