11.3 System Generator for DSP - Why do I see an instantiated register called "xlpersistentdff" in my System Generator for DSP design?

AR#	24257	Search For Another Answer
Topic	SW-SysGen
Last Updated	09/10/2009
Status	Active

Description

Keywords: MATLAB, Simulink, register, persistent, SysGen

Why do I see an instantiated register called "xlpersistentdff" in my System Generator for DSP design?

Solution

The register is a persistent register which is placed in every design to make sure that there is at least one synchronous element present in every design. This register will be present in the top-level HDL file, but it is not part of the user design and can be safely ignored.