Direct register access exposes every hardware detail to the calling code. A peripheral driver concentrates those details behind operations meaningful to the rest of the program.

For example, application code may call

set_motor_enable(true)

rather than know which GPIO port, register and bit implement that signal on one board.

A useful driver owns device-specific sequencing, status interpretation and register manipulation while exposing a smaller contract to its clients. This reduces the number of modules that depend on one particular chip or board layout.

A hardware abstraction layer (HAL) can standardize common capabilities across related targets. The abstraction should reflect behavior that can genuinely be implemented across those targets rather than hide important differences behind misleadingly identical names.

Not every register needs a wrapper. Abstraction is valuable when it creates a stable boundary for application logic, testing or portability.

Drivers therefore connect low-level hardware contracts to software interfaces that can evolve independently.