1. Apparatus for measuring the power consumed by a processing unit processor bus during predetermined period of time, the apparatus comprising: a central processing unit, the central processing unit including a trace port, the central processing unit executing a program, the central processing unit applying to a trace port trace signals resulting from the execution of the program; a trace unit for receiving trace information from the trace port; a first memory unit portion coupled to the trace unit for storing the trace information; a second memory portion for storing a simulation model of the central processing unit; and a processor coupled to the first and the second memory portion; the processor determining power consumption for the program execution of the central processing unit.