Why is there an Error (20783): Open Drain option is set to 'ON' for pin [pin name], but the setting is not supported by I/O standard 1.2-V. File: [location]?

Description

You may encounter this error when migrating a design for the Agilex™ 3 FPGA and Agilex™ 5 FPGA device families from Quartus® Prime Edition Software version 25.1.1 or earlier and restoring from a .QAR file to version 25.3.
 
Starting with Quartus® Prime Edition Software version 25.3, the default setting for the AUTO_OPEN_DRAIN assignment for Agilex™ 3 and Agilex™ 5 families changed from ON to OFF, whereas previous versions had it set to ON by default. When a project is restored from a .QAR file, it retains the default settings from the Quartus version in which it was created, not the version used for restoration. As a result, the restored project continues to use AUTO_OPEN_DRAIN set to ON, since that was the default at the time the project was archived.

Resolution

To work around this problem, follow these steps:
 
1. Modify the project's QSF settings to set the assignment for AUTO_OPEN_DRAIN to OFF
 
set_global_assignment -name AUTO_OPEN_DRAIN OFF
 
2. Remove the AUTO_OPEN_DRAIN ON line from the project QDF file (Quartus Default Settings File) that is created when restoring the project to Quartus® Prime Edition Software version 25.3.
 
This problem is fixed in the Quartus® Prime Pro Edition Software version 25.3 and later.