A clock synchronization method for ima platform

Abstract

The invention provides an IMA platform clock synchronization method. The method includes the following steps that (1) time synchronization messages are detected and received, when one wrong time synchronization message is detected, a synchronization error is recorded, and the message is discarded; (2) when a main clock node receives the absolute global time of the system, the time is converted into a piece of 64-bit time data, and accordingly the RTCs value of a main clock is calibrated or updated; meanwhile, in accordance with system communication scheduling, system reference time is 'broadcasted' to a local clock (switching node) connected with the system in each fixed time period. According to the layering distribution type clock relative synchronization technology and method, all function modules (including network switch) of the IMA system and other avionics function devices / subsystems are made to be kept within a certain error allowed range relative to the system reference time to work coordinately, synchronously and orderly; meanwhile, in order to prevent the phenomenon that all node clocks bring time deviation to the system with the passage of time, all the nodes receive time calibration of the system periodically.

Description

technical field [0001] The invention belongs to the airborne embedded computer system technology, realizes a clock synchronization method of the core processing platform of an integrated modular avionics system (IMA), and is mainly applied to the time between each node (equipment or module) of the new generation IMA system Synchronize. Background technique [0002] The introduction of integrated and networked technologies makes traditional avionics functional equipment or subsystems "condensed" into a functional module of today's integrated processing platform, and is interconnected through a switched network to form a complex distributed asynchronous real-time processing system. The execution of system tasks depends on the division of labor and cooperation of each node (such as function processing, data calculation, graphics processing, etc.), and real-time communication can be effectively completed. How to ensure the time synchronization between the asynchronous working ...

AI Technical Summary

Problems solved by technology

[0003] The traditional shared bus avionics system, due to its centralized control, unified reference clock and low time resolution, can no longer meet the time synchronization requirements of modern complex networked airborne distributed real-time processing systems; in addition, the airborne data network is a A switched asynchronous communication network, its protocol does not require time synchronization between system nodes, and the application of the IMA system requires its functional modules, equipment / subsystems to work in an orderly manner under a unified reference time base to jointly complete the system real-time Tasks, such as time correlation recording, data validity judgment, correctness confirmation of timing results, etc.

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