Instruction Cycle - Initiating The Cycle

Initiating The Cycle

The cycle starts immediately when power is applied to the system using an initial PC value that is predefined for the system architecture (in Intel IA-32 CPUs, for instance, the predefined PC value is 0xfffffff0). Typically this address points to instructions in a read-only memory (ROM) which begin the process of loading the operating system. (That loading process is called booting.)