Patent ID: 7577780

Claim:
A fine-grained bandwidth control arbiter is used to decide the usage priority of a shared bus when multiple masters propose bus usage requests on a shared bus, the masters possess respectively real-time requirement and bandwidth requirement and are preset with tickets respectively, the arbiter comprising: a real-time handler configured to judge if the bus usage requests are urgent when the bus usage requests include real-time requirements and to grant the most urgent bus usage request; a bandwidth regulator connected to the real-time handler and configured to detect satisfaction of the bandwidth requirements of the masters, and within a certain period of time, to limit the bus usage requests of the masters with the bandwidth requirements satisfied, wherein when the bandwidth requirements of one or more of the masters are satisfied in a certain period of time, the bandwidth regulator temporarily limits the bus usage request sent out by the one or more of the masters and yields the bus usage priority to the other one or more masters of which the bandwidth requirements are not satisfied; a lottery manager with tuned weight connected to the bandwidth regulator and configured to grant the usage request of one of the masters in a weighted random way based on the tickets and determination of the satisfaction of the bandwidth requirements of the masters determined by the bandwidth regulator; and a plurality of AND gates respectively corresponding to the maters, wherein each of the AND gate receives a corresponding one of the bus usage requests and a corresponding one of limiting signals from the bandwidth regulator and outputs a resulting signal to the lottery manager with tuned weight to determine whether to limit the bus usage request of the corresponding one of the masters, wherein when there is no urgent bus usage request, the real-time handler is not in action.