METHOD HAVING DYNAMICALLY SCALABLE CLOCK DOMAIN TO SELECTIVELY INTERCONNECT SUBSYSTEMS THROUGH SYNCHRONOUS BUS, AND SYSTEM THEREOF

摘要

PROBLEM TO BE SOLVED: To solve problems which are necessary to improve flexibility of operating frequencies of a synchronous bus.;SOLUTION: In one mode of this invention, the method for communicating between subsystems coupled to a bus of a computer system on an integrated circuit chip includes a step which makes the subsystems operate by independent clock frequencies when the subsystems do not communicate each other through the bus. A selected pair of the subsystems is made to operate by a shared clock frequency by selectively varying the frequency of a clock signal supplied to the subsystems, and the selected subsystems are enabled to communicate each other by the shared clock frequency through the bus (The clock frequency is different when the pair of subsystems is different.); and the subsystem are made to enable to operate by an independent clock frequency when the subsystem does not communicate to other subsystem. Communication between subsystems is performed by bus-based protocol; as the result, when a subsystem is permitted to access to the bus, the subsystem can use the bus exclusively.;COPYRIGHT: (C)2004,JPO&NCIPI