The Design And Implement Of Data Record And Replay Based On QNX Real-time Muti-channel Digital Synchronized Log

The Multi-channel Digital Synchronized Log (MDSL) is a hi-tech product developed by Institute of Image & Graphics, Sichuan University, which is used mainly for recording synchronously the radar data and the dialogue between pilots and the control tower for airdrome and airline companies. The voice and radar data in MDSL is an important testimony in the analysis of aero accident, so the reliability of recording and the synchronization of voice data and radar data reordered are the first requirement for the MDSL system. The system is a typical real time system. Author finish the analyzing of the requirement of the MDSL system's data record and replay by the SART (Structured Analysis for Real Time) successfully, that ensure the design and coding effective. Author designed and implemented the record-unit with mutil-thread by the method of Structured Design. The most difficult task of the design is to arrange the privilege of all tasks to ensure the system's response to external real-time event timely, and to avoid the deadlock and to enhance the ability of fault-tolerance. Author finish the Design and Implement of data record and replay.In the data replay part, I focus in resolving the problem of display and progress the efficiency and effective of radar's object replaying.