SERIAL TIME-DIVISION-MULTIPLEXED BUS WITH BIDIRECTIONAL SYNCHRONIZATION/CONTROL WORD LINE

摘要

One feature pertains to the synchronization of a serial time-division-multiplexed bus interconnecting an audio processing subsystem (i.e. a local node) with an audio coder-decoder (CODEC) subsystem (i.e. a remote node.) Control signals are transmitted along a bidirectional transmission line of the bus from the audio processing subsystem to the audio CODEC subsystem. The audio processing subsystem tracks an internal state machine phase count as the control signals are transmitted. The audio CODEC subsystem also tracks an internal state machine phase count as the signals are received. Transmission of control signals by the audio processing subsystem is periodically paused or suspended for a fixed interval of time based on the phase count to allow the audio CODEC subsystem to send a synchronization indicator signal back to the audio processing subsystem, which the audio processing subsystem uses to verify synchronization. This may be performed, for example, once every one hundred-twenty phase counts.