1553B总线上消息的实时调度

为了优化1553B总线传输性能,降低总线上消息传输的延迟时间,讨论了周期消息和非周期消息混合传输情况下总线上的消息调度策略。首先,借鉴周期任务的调度模型对周期消息进行建模,提出了改进的速率单调消息调度算法。然后,利用排队论建立非周期消息的M/M/1排队模型,定量分析了1553B总线的平均响应时间和总线利用率等时间性能参数,并对非周期消息的延迟时间进行优化,推导出总线最优服务率和最小平均延迟时间的计算公式,给出了非周期消息的调度算法。最后,对上述算法在消息混合传输下的可调度性进行了验证。实验结果表明,在总线利用率达96%时,混合消息的平均响应时间为0.713ms。在消息混合传输的情况下,非周期消息的平均响应时间和M/M/1排队模型下理想的非周期响应时间偏差不超过10%。上述算法时间响应特性良好,能够保证周期消息和非周期消息的实时调度。

The emulational device for opto-electric detecting based on LabVIEW and c language

In order to optimize the transmission performance of 1553B bus and to reduce the transmission delay time of messages on the bus, a scheduling strategy for the mixed periodic and aperiodic messages on the bus was proposed. Firstly, a model for the periodic messages was established according to the scheduling model of periodic tasks, and an improved rate-monotonic scheduling algorithm was presented. Then, the M/M/1 queuing model for aperiodic messages was established based on the queue theory, and the time pe...