Apparatus for transmitting an anisochronic data stream on an isochronic transmission route
To transmit an anisochronic data stream on an isochronic transmission route with a plurality of channels over a transmission network, a number of channels is reserved by the transmitter before beginning the transmission, where the sum of the transmission capacities of the reserved channels just exceeds the bandwidth of the asynchronous data stream. During the course of transmission, the data of the anisochronic data stream are formed into packets; each packet is transmitted over the reserved channels. After a packet has been sent, unused portions of the reserved channels are filled with filler data that is discarded at the receiver, until sufficient data are again available at the transmitter to begin transmission of the next packet.
1. A method of transmitting an anisochronic data stream from a data source to a data sink over a isochronic transmission network having with a plurality of channels, comprising:
receiving data from the data source, and reserving at least two of the plurality of channels to provide reserved channels for transmission of data from the transmitter onto the transmission network, where the cumulative transmission capacities of the reserved channels exceeds the bandwidth of the asynchronous data stream;
partitioning data of the anisochronic data stream into packets;
filling bit locations of the packets not required to transmit the anischronic data with filler data, and providing packetized data indicative thereof; and
providing the packetized data for transmission over at least one reserved channel of the transmission network.
2. The method of claim 1 , where the step of providing the packetized data comprises inserting a synchronization pattern into the packetized data before data associated with the anisochronic data, to identify the portions of the data of the packetized data as data indicative of the anischronic data.
3. The method of claim 1 , where the packets each have the same data quantity.
4. The method of claim 1 , where the reserved channels are time multiplexed channels, and the transmission network includes a time division multiplexed bus.
5. The method of claim 1 , where the anisochronic data stream comprises audio data.
6. The method of claim 1 , where then transmission network comprises a MOST network.
7. The method of claim 6 , where the MOST network operates at a frequency of 44.1 MHz, and the anisochronic data stream has a frequency of 48 MHz or an integer multiple thereof.
8. The method of claim 1 , where the data source comprises a DVD player.
9. The method of claim 1 , where the data source comprises a CD player.
10. A data transmission system, comprising:
a data bus;
a data source that provides an anisochronic data stream;
a transmitter that receives the anischronic data stream, assigns a plurality of channels associated with the data bus for transmission of data indicative of the anischronic data stream, partitions the anischronic data into a plurality of packets, and fills unused bit locations of each packet with filler data, and provides output packets indicative thereof;
a first bus interface that receives the output packets and transmits the output packets onto the data bus;
a second bus interface that receives an output packets on the data bus, and provides input packets indicative thereof; and
a receiver that receives and processes the input packets to recover the anischronic data stream, and provides a recovered anischronic data stream indicative thereof.
11. The data transmission system of claim 10 , where the data bus includes a MOST bus.
12. The data transmission system of claim 11 , where the data source includes a DVD player.
13. The data transmission system of claim 10 , where the MOST bus operates at a frequency of 44.1 kHz, and the anisochronic data stream has a frequency of 48 kHz or an integer multiple thereof.
14. The data transmission system of claim 13 , where the reserved channels are time multiplexed channels, and the data bus is configured and arranged as a time division multiplexed bus.
15. The data transmission system of claim 10 , further comprising an intermediate memory device where the transmitter stores data indicative of the anischronic data stream, and when a certain amount of data associated with the anischronic data stream has been stored in the intermediate memory, the transmitter initiates providing the output packets.
16. The data transmission system of claim 15 , where the transmitter also provides to the first bus interface a synchronization pattern that is transmitted over the data bus prior to the packets associated with the anischronic data stream to identify to the receiver the data associated with the anischronic data stream.
17. An apparatus for transmitting an anisochronic data stream from a data source to a data sink over a isochronic transmission network having with a plurality of channels, comprising:
means for receiving data from the data source, and for reserving at least two of the plurality of channels to provide reserved channels for transmission of data from the transmitter onto the transmission network, where the cumulative transmission capacities of the reserved channels exceeds the bandwidth of the asynchronous data stream;
means for partitioning data of the anisochronic data stream into packets;
means for providing bit locations of the packets not required to transmit the anischronic data with filler data, and for providing packetized data indicative thereof; and
means for providing the packetized data for transmission over at least one reserved channel of the transmission network.