# Register Layer

The UVM register layer defines several base classes that, when properly extended, abstract the read/write operations to registers and memories in a design-under-verification.

A register model is typically composed of a hierarchy of blocks that usually map to the design hierarchy. Blocks contain registers, register files and memories.

The UVM register layer classes are not usable as-is. They only provide generic and introspection capabilities. They must be specialized via extensions to provide an abstract view that corresponds to the actual registers and memories in a design. Due to the large number of registers in a design and the numerous small details involved in properly configuring the UVM register layer classes, this specialization is normally done by a model generator. Model generators work from a specification of the registers and memories in a design and are thus able to provide an up-to-date, correct-by-construction register model. Model generators are outside the scope of the UVM library.

The class diagram of a register layer model is shown below.

Summary

Register Layer
The UVM register layer defines several base classes that, when properly extended, abstract the read/write operations to registers and memories in a design-under-verification.