Microcontroller energy profiler

A method is disclosed to estimate energy consumed by a component in a microcontroller during operation including identifying "event" activities, where the energy consumed by the component may be determined by the number of events executed by the component, and "duration" activities, where the energy consumed may be determined by the duration of time required to execute of the activity, and determining the energy consumed by the component based on the number of events/duration of time and an energy coefficient which corresponds to the amount of energy consumed by the component to execute the activity, under given operating conditions. In an embodiment, data transfers at a bus interface may represent event activities. Apparatus to estimate the energy consumed is disclosed including bus monitors to receive signals representing data transfers at a bus interface and provide signals indicating the number of data transfers executed.