Clock synchronization of data streams
View Patent ↗A system synchronizes data flow between a first device and a second device. The system includes a data link that connects two or more devices that are capable of sending and receiving data through a bus. A capture device senses and transfer information through the bus. A ring buffer temporarily stores data transmitted through the bus. A read controller copies or reconstructs data in a length that is different from the length of the data received. A monitor detects underflow or overflow conditions into or out of the ring buffer and compensates for clock drift.
1. A system that synchronizes data flow between a first device and a second device comprising:
a data link that couples two or more devices that are capable of sending and receiving data through a bus system;
a capture device in communication with the data link configured to sense and transfer information through the bus system;
a ring buffer in communication with the capture device that temporarily stores data received by the data link;
a write controller that writes data to the ring buffer;
a read controller in communication with the ring buffer that copies or reconstructs data in a second length that is different from a first length of data received by the capture device;
a playback device that transmits data to an output port; and
a monitor that detects an underflow or an overflow condition into or out of the ring buffer and compensates for a clock drift by transmitting a blocking call to the capture device when an overflow condition is detected and compensates for the clock drift by transmitting a blocking call to the playback device when an underflow condition is detected.
2. The system of claim 1 where the data link comprises an external bus.
3. The system of claim 1 further comprising a device driver in communication with the data link.
4. The system of claim 1 where the device driver comprises a translator that translates a data format into a different data format to ensure operative compatibility between two different devices.
5. The system of claim 1 where the ring buffer comprises a first-in, first out storage device.
6. The system of claim 1 where the monitor is configured to construct or parse data to be transmitted by the playback device.
7. The system of claim 1 where the capture device is configured to receive data processed at a different rate than the rate the data is transmitted by the playback device.
8. The system of claim 1 where the ring buffer comprises a contiguous block of memory.
9. The system of claim 1 where the ring buffer comprises a non-contiguous block of memory.
10. The system of claim 1 where the ring buffer comprises overflow logic that prevents an access pointer from moving out of a predetermined memory address range.
11. The system of claim 10 where the overflow logic is configured to be disabled through a software instruction.
12. The system of claim 1 where the monitor is configured to derive a compensation time through a windowing function.
13. The system of claim 1 where the monitor compensates for the clock drift at a synchronous basis.
14. The system of claim 1 where the monitor compensates for clock drift at a asynchronous basis.
15. A system that synchronizes data flow between a first device and a second device comprising:
a capture device in communication a data link configured to sense and transfer information;
a synchronizer in communication with the capture device that stores data received through the capture device;
a read controller in communication with a ring buffer that copies data in a second length that is different from a length received by the capture device; and
a monitor that detects an underflow or an overflow condition into or out of the synchronizer and compensates for a clock drift by transmitting a blocking call to the capture device when an overflow condition is detected and compensates for the clock drift by transmitting a blocking call to a playback device when an underflow condition is detected.
16. The system of claim 15 where the capture device is in communication with a device driver where the device driver comprises a translator that translates a data format into a different data format to ensure operative compatibility between two different devices.
17. The system of claim 15 where the monitor compensates for clock drift at a asynchronous interval.
18. The system of claim 15 where the synchronizer is coupled to a vehicle.
19. The system of claim 15 where the synchronizer is coupled to a publicly accessible network.
20. A system that synchronizes data flow between a first device and a second device comprising:
a capture device in communication with a data link configured to sense and transfer information;
a synchronizer in communication with the capture device that stores data received through the capture device;
a read controller in communication with the synchronizer that copies data in a second length that is different from a length received by the capture device; and
means that detects an underflow or an overflow condition into or out of the synchronizer and compensates for a clock drift by transmitting a blocking call to the capture device when an overflow condition is detected and compensates for the clock drift by transmitting a blocking call to a playback device when an underflow condition is detected.
21. The system of claim 20 where the capture device is in communication with a device driver where the device driver comprises a means that translates a data format into a different data format to ensure operative compatibility between two different devices.
22. The system of claim 20 where the means that detects the underflow or overflow condition compensates for clock drift at an asynchronous interval.
23. The system of claim 20 where the synchronizer is coupled to a vehicle.
24. The system of claim 20 where the synchronizer is in communication with a publicly accessible network.
25. A system that synchronizes data flow between a first device and a second device comprising:
a capture device in communication with a data link configured to sense and transfer information;
a synchronizer in communication with the capture device that stores data received through the capture device;
a read controller in communication with the synchronizer that copies data in a second length that is different from a length received by the capture device; and
a monitor that detects an underflow or an overflow condition into or out of the synchronizer and compensates for a clock drift by transmitting a blocking call to the capture device when an overflow condition is detected and compensates for the clock drift by transmitting a blocking call to a playback device when an underflow condition is detected;
where the monitor is configured to transmit the blocking call to the capture device to prevent the capture device from obtaining data from the first device, where the monitor is configured to transmit the blocking call to the playback device to prevent the playback device from transmitting data to the second device.
26. A data synchronization system, comprising:
a capture device that receives data from a first external device;
a playback device that sends data to a second external device;
a buffer in communication with the capture device and the playback device, where the buffer stores data received from the first external device and provides data to the playback device for transmission to the second external device; and
a buffer monitor configured to transmit a blocking call to the capture device to prevent the capture device from obtaining additional data from the first external device in a buffer overflow condition, where the buffer monitor is configured to transmit a blocking call to the playback device to prevent the playback device from transmitting additional data to the second external device in a buffer underflow condition;
where the capture device, playback device, buffer, and buffer monitor comprise portions of a unitary device that provides a data flow interface between the first external device and the second external device.