Introduction

Although the official SystemRDL spec defines numerous properties that allow you to define complex register map structures, sometimes they are not enough to accurately describe a necessary feature. Fortunately the SystemRDL spec allows the language to be extended using “User Defined Properties” (UDPs). The PeakRDL-rust tool understands several UDPs that are described in this section.

To enable these UDPs, compile this RDL file prior to the rest of your design: udps.rdl.

Any UDPs encountered that are not listed here are ignored.

Summary of UDPs

Name	Component	Type	Description
is_signed	field	boolean	Defines the signedness of a field. See: Signed Fields.
intwidth	field	unsigned integer	Defines the number of integer bits in the fixed-point representation of a field. See: Fixed-Point Fields.
fracwidth	field	unsigned integer	Defines the number of fractional bits in the fixed-point representation of a field. See: Fixed-Point Fields.