Patent ID: 6216052
Filing Date: 2001-04-10
Classification: H03F

Abstract:
A bus controller comprising:an interface for coupling said bus controller to a bus and providing signals to and from said bus;a bus monitor coupled to said interface and configured to receive signals on said bus and to monitor said bus for the presence of clock activity, audio data, or errors in said audio data; anda suppression unit coupled to said bus monitor and configured to control volume of a powered loudspeaker on said bus responsive to an indication from said bus monitor of an absence of said clock activity, said audio data, or a presence of said errors in said audio data on said bus, wherein said suppression unit is configured to gradually ramp said volume of said powered loudspeaker from a first predetermined level to a second predetermined level responsive to said indication of an absence of said clock activity, said audio data, or a presence of said errors in said audio data on said bus; and wherein said suppression unit is configured to turn off power to said powered loudspeaker after said volume of said powered loudspeaker has been adjusted to said second predetermined level;wherein said suppression unit is configured to restore said power to said powered loudspeaker a predetermined time after said power has been turned off or upon said bus monitor detecting the presence of said clock activity, said audio data, or the absence of said errors on said bus;said suppression unit is further configured to ramp said volume of said powered loudspeaker from said second predetermined level to said first predetermined level after said power has been restored to said powered loudspeaker.