Why do unused transceiver channels in my Intel® Stratix®10 L- or H-Tile devices degrade over time?

Unused transceiver channels in your Intel® Stratix® 10 L- or H-Tile transceivers may degrade over time when using the Intel® Quartus® Prime software version 18.1.0 and earlier.

The Intel Quartus Prime software generates a warning message if your design contains unused transceiver channels. The warning message states that performance of unused channels may degrade over time if not properly preserved with the following Quartus Settings File (QSF) assigment.

Global Assignment

set_global_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON

Pin Specific Assignment

set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to pin_name

For example, if PIN_U34 is used, is specified as U34 and not PIN_U34. Fitter will ignore assignment if PIN_U34 is used as <pin_name>.

In the Intel Quartus Prime software version 18.1.0 and earlier, the QSF assignment is incorrect.

To preserve the performance of unused transceiver channels in Intel® Stratix® 10 L- or H-Tile transceivers, you should recompile your design in Intel® Quartus® Prime software version 18.1.1 or later.