Patent ID: 8527682
Filing Date: 2013-09-03
Classification: G06F

Abstract:
1. A bus controller for controlling a bus communication system wherein each initiator of a plurality of initiators connected to a bus generates and sends a request signal to request use of the bus at predetermined intervals, and upon being granted use of the bus in response to the request signal, sends a command signal to instruct execution of a predetermined process to a target connected to the bus, and when the each initiator determines that the predetermined process is not to be executed by the target, the each initiator sends, upon being granted use of the bus again, the command signal to the target, the bus controller comprising: a bus control unit configured to, upon receiving the request signal from the each initiator, grant use of the bus to the each initiator based on predetermined priorities; and a mask generating unit configured to mask the request signal generated by the each initiator to control a timing, at which the request signal is sent from the each initiator, to be aperiodic, wherein the mask generating unit includes a mask interval setting unit configured to set, as a mask interval, an interval for masking the request signal generated by the each initiator; a mask condition setting unit configured to set, as a plurality of mask conditions, a plurality of combinations of initiators to be subject to masking, the plurality of mask conditions including as many excluding mask conditions as the plurality of initiators, each of the excluding mask conditions corresponding to each of the plurality of initiators and being a combination of initiators to be subject to masking from which only the each of the plurality of initiators corresponding to the each of the excluding mask conditions is excluded among the plurality of initiators; and a counter of an initiator mask ID (identifier) corresponding to each of the plurality of mask conditions set by the mask condition setting unit, and wherein the mask generating unit, at each mask interval set by the mask interval setting unit, counts up the counter, determines a selected initiator to be subject to masking among the plurality of initiators, the selected initiator having the initiator mask ID indicated by the counter, and masks a request signal generated by the selected initiator.