A subscriber of a wired data network, in particular of a local bus system, having internal clock generator for generating a clock generator signal having a clock generator frequency for the subscriber, a receive circuit for receiving a serial receive data stream, a processing circuit for inputting parallel receive data and for outputting parallel transmit data, and a transmit circuit for transmitting a serial transmit data stream. The receive circuit has a serial-to-parallel converter for converting serial receive data of the serial receive data stream into the parallel receive data. The receive circuit has a synchronization unit for synchronizing the internal clock generator to the data clock frequency contained in the serial receive data stream. The synchronization unit is configured for detecting transitions in the received serial receive data stream and for controlling the clock generator frequency of the internal clock generator as a function of the detected transitions.

Example systems, apparatus, and methods receive audio information including a plurality of frames from a source device, wherein each frame of the plurality of frames includes one or more audio samples and a time stamp indicating when to play the one or more audio samples of the respective frame. In an example, the time stamp is updated for each of the plurality of frames using a time differential value determined between clock information received from the source device and clock information associated with the device. The updated time stamp is stored for each of the plurality of frames, and the audio information is output based on the plurality of frames and associated updated time stamps. A number of samples per frame to be output is adjusted based on a comparison between the updated time stamp for the frame and a predicted time value for play back of the frame.

A method of transmitting packets between a plurality of nodes of a network. The method comprising in each of a plurality of data timeslots, transmitting a data packet with one of the plurality of nodes and listening to receive the data packet with the remainder of the plurality of nodes. The method further comprising in each of one or more parity timeslots following the plurality of data timeslots, transmitting a parity packet with one or more of the plurality of nodes and listening to receive the parity packet with the remainder of the plurality of nodes. Each parity packet is derived from a set of the data packets transmitted during the plurality of data timeslots.

Individual clock adjustments between electronic devices are typically based around a round-trip time (RTT) measurement of the reference message between initiating and the receiving devices. With increasing expectations of clock synchronization accuracy, as well as widespread use of wireless data networks, the presently disclosed technology provides a dedicated clock synchronization network that yields a fixed delay between hops and within associated devices of a dedicated clock synchronization network. By accounting for the known delays between hops and within associated devices of the dedicated clock synchronization network, better clock synchronization accuracy can be achieved than prior art techniques that estimate latency based on an RTT measurement.

A system is described for maintaining synchrony of operations among a plurality of devices that have independent clocking arrangements. The system includes a task distribution device that distributes tasks to a synchrony group comprising a plurality of devices that are to perform the tasks distributed by the task distribution device in synchrony. The task distribution device distributes each task to the members of the synchrony group over a network. Each task is associated with a time stamp that indicates a time, relative to a clock maintained by the task distribution device, at which the members of the synchrony group are to execute the task. Each member of the synchrony group periodically obtains from the task distribution device an indication of the current time indicated by its clock, determines a time differential between the task distribution device's clock and its respective clock and determines therefrom a time at which, according to its respective clock, the time stamp indicates that it is to execute the task.

Example systems, apparatus, and methods receive audio information including a plurality of frames from a source device, wherein each frame of the plurality of frames includes one or more audio samples and a time stamp indicating when to play the one or more audio samples of the respective frame. In an example, the time stamp is updated for each of the plurality of frames using a time differential value determined between clock information received from the source device and clock information associated with the device. The updated time stamp is stored for each of the plurality of frames, and the audio information is output based on the plurality of frames and associated updated time stamps. A number of samples per frame to be output is adjusted based on a comparison between the updated time stamp for the frame and a predicted time value for play back of the frame.

A system is described for maintaining synchrony of operations among a plurality of devices that have independent clocking arrangements. The system includes a task distribution device that distributes tasks to a synchrony group comprising a plurality of devices that are to perform the tasks distributed by the task distribution device in synchrony. The task distribution device distributes each task to the members of the synchrony group over a network. Each task is associated with a time stamp that indicates a time, relative to a clock maintained by the task distribution device, at which the members of the synchrony group are to execute the task. Each member of the synchrony group periodically obtains from the task distribution device an indication of the current time indicated by its clock, determines a time differential between the task distribution device's clock and its respective clock and determines therefrom a time at which, according to its respective clock, the time stamp indicates that it is to execute the task.

A system is described for maintaining synchrony of operations among a plurality of devices that have independent clocking arrangements. The system includes a task distribution device that distributes tasks to a synchrony group comprising a plurality of devices that are to perform the tasks distributed by the task distribution device in synchrony. The task distribution device distributes each task to the members of the synchrony group over a network. Each task is associated with a time stamp that indicates a time, relative to a clock maintained by the task distribution device, at which the members of the synchrony group are to execute the task. Each member of the synchrony group periodically obtains from the task distribution device an indication of the current time indicated by its clock, determines a time differential between the task distribution device's clock and its respective clock and determines therefrom a time at which, according to its respective clock, the time stamp indicates that it is to execute the task.

Time stamp replication within wireless networks is described. In an embodiment, a wireless station receives an input time stamp and uses this input time stamp to generate an output time stamp. The wireless station transmits the output time stamp to wireless stations in one of a number of groups which make up the wireless network. The output time stamp is generated to compensate for delays between receiving the input time stamp and transmitting the output time stamp such that output time stamp which is transmitted at a time T corresponds to the value that the input time stamp would have had if it had been received at time T (and not at a time earlier than T). This may, therefore, reduce or eliminate independent time stamp errors and jitter caused by multiple disparate systems and processes.

The present technology relates to a transmission device, a transmission method, a reception device, and a reception method that permit efficient transfer of time and other information. The transmission device generates a physical layer frame having preambles and a payload that includes, in the preamble, time information representing time of a given position in a stream of physical layer frames and transmits the physical layer frame. The reception device receives the physical layer frame and performs processes using time information. The present technology is applicable, for example, to IP packet broadcasting.