Ordering Your Constraints - 2022.1 English

Vivado Design Suite User Guide: Using Constraints (UG903)

Document ID
UG903
Release Date
2022-06-01
Version
2022.1 English
Because XDC constraints are applied sequentially, and are prioritized based on clear precedence rules, you must review the order of your constraints carefully. For more information, see XDC Precedence.
Note: If multiple physical constraints are conflicting, the latest constraint wins. For example, if an I/O port gets assigned a different location (LOC) through multiple XDC files, the latest location assigned to the port takes precedence.

The Vivado IDE provides full visibility into your design. To validate your constraints step by step:

  1. Run the appropriate report commands.
  2. Review the messages in the Tcl Console or the Messages window.