IEMEK Journal of Embedded Systems and Applications (대한임베디드공학회논문지)

Institute of Embedded Engineering of Korea (대한임베디드공학회)
권호 표지
DOI QR코드

DOI QR Code

Recursive Time Synchronization Method Based on GPIO Signal Delay Compensation and EMA Filter

GPIO EMA 신호 지연 보상 및 필터 기반 재귀적 시간 동기화 기법

  • Received : 2019.10.28
  • Accepted : 2019.11.29
  • Published : 2020.02.29
Download PDF
⟨ Previous Next ⟩

Abstract

We propose a system time synchronization method between embedded Linux-based distributed control devices by using Transmission Control Protocol (TCP) communication and General Purpose Input Output (GPIO) device. The GPIO signal is used as the trigger signal for synchronization and the TCP communication is used to transfer the system time of master Linux, which serves as the reference clock, to slave Linux. Precise synchronization performance is achieved by measuring and compensating for the propagation delay of GPIO signal and the acquisition and setting latency of Linux system time. We build an experimental setup consisting of two embedded Linux systems, and perform extensive experiments to verify the performance of the proposed synchronization method.

Keywords

References

  1. R. Cochran, C. Marinescu, C. Riesch, "Synchronizing the Linux System Time to a PTP Hardware Clock," Proceedings of IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication, pp. 87-92, 2011.
  2. D.B. Stewart, "Measuring Execution Time and Real-Time Performance," Proceedgins of Embedded Systems Conference, pp. 341-361, 2006.
  3. R.L. Scheiterer, C. Na, D. Obradovic, G. Steindl, "Synchronization Performance of the Precision Time Protocol in Industrial Automation Networks," Journal of IEEE Transactions on Instrumentation and Measurement, Vol 58, No. 6, pp.87-92, 2009. https://doi.org/10.1109/TIM.2008.928402
  4. P. Ohly, D.N. Lombard, K.B. Stanton, "Hardware Assisted Precision Time Protocol. Design and Case Study," Proceedings of the 9th LCI International Conference on High-Performance Clustered Computing, pp.121-131, 2008.
  5. Y.K. Lee, S.H. Yang, C.B. Lee, J.G. Lee, Y.M. Park, M.S. Lee, "Evaluation of Synchronization Performance with PTP," Journal of Institute of Control, Robotics and Systems, Vol. 20, No. 6, pp. 669-675, 2014. https://doi.org/10.5302/J.ICROS.2014.14.0025
  6. S.W. Park, I.S. Kim, D.I. Lee, "Implementation of IEEE 1588 for Clock Synchronization," Journal of Korean Institute of Communicatios and Information Sciences, Vol. 39, No. 2, pp. 123-132, 2014 (In Korean).
  7. T. Kovacshazy, T. Tusori, D. Vincze, "Prototype Implementation and Performance of Time-based Distributed Scheduling on Linux for Real-Time Cyber-Physical Systems," Proceedings of IEEE International Symposium on Precision Clock Synchronization for Measurement, Control, and Communication, pp. 1-6, 2018.
  8. S.M. Park, H.J. Kim, H.W. Kim, C.N. Cho, J.Y. Choi, "Synchronization Improvement of Distributed Clocks in EtherCAT Networks," Jouenal of IEEE Communications Letter, Vol. 21, No. 6, pp. 1277-1280, 2017. https://doi.org/10.1109/LCOMM.2017.2668400