Application Research Of IEEE1394 On Real-time And Dynamic Resource Management

IEEE 1394 serial bus has been widely used in consumer electronics applications, and now it's applixation has also extended to industrial control, aerospace and military and other fields. These new fields of application not only makes the IEEE1394 bus's work environment becomes more complex, but also ask for higher real-time and more quality of services requirements. This thesis makes the IEEE1394 bus can accommodate these new application areas and the main work as follows:Traditional IEEE1394 subsystem may increase the delay of interruption and couse packet priority inversion when applied in real-time environment. The paper presents several methods to improve real-time performance of IEEE 1394:Interrupt service routine only to send signal to activate the interrupt service task, and then interrupt service task distributes handing of the event to tasks with different priority, so it can reduce interrupt latency of the system. By adding custom tags in the header of Asynchronous packet to extend the IEEE1394 protocol, and let the packets have priority tag. And then different priority packets will be processed by different priority tasks. Because of the high-priority tasks can executive by priority preemptive scheduling. By topology optimization can make some of the nodes has a higher natural priority when bus arbitration. We have realized the IEEE1394 subsystem in VxWorks real-time operating sysem, and test it. The results showed that the response time of high-priority packets shorter and more stable.Traditional IEEE1394 subsystem use of the bandwidth in a fixed-mode, and this can not guarantee that asynchronous transfer and bandwidth of a single node. This paper proposes a data transmission control model, and used for asynchronous bandwidth reservation and assessment the waiting time of asynchronous transfer. We designed a bandwidth management and dynamic scheduling module. This module contains main control task and collaborative tasks. The collaborative tasks manage the bandwidth of nodes which it is in, and the main control task manages collaborative tasks to manage the whole resource of system. Through the module we quantitative distribution channel, dynamic scheduling, preemption recovery, so as to dynamically reserve bandwidth for asynchronous transfer.Finally, a resource allocation management module was implemented in the IEEE 1394 system, it use to control data transmission. The results show that it can reserve bus bandwidth for asynchronous services.IEEE1394 protocol allows used for devices to transmit data by isochronous or asynchronous, when specific to a particular application, it also need to imply its related application protocols, such as AV/C, SBP2, etc.IEEE1394 disk device is not as VxWorks real-time embedded operating system standard equipment, if we want use it in VxWorks, we have to design the SBP2 disk drive. So this paper analyzes the SBP2 protocol and its implementation, and designed SBP2 disk storage systems based on IEEE1394 protocol, connect it as block device drivers to file system of VxWorks operating system seamlessly.