Study On The Application Of VxWorks To High Speed CPCI Data Acquisiton System

In this thesis, the application of VxWorks to high speed cPCI data acquisition system is investigated systematically against the background of space borne distributed SAR radar simulation system. This system is used to support the spaceborne distributed SAR radar signal simulation system, which can be used to analysis the various characteristics of the object's echo or the interfering signal and thus can supply an actual model and test bench of the spaceboren SRA for the designer.The work of this thesis includes three parts as follows:Aiming at the implementation of the driver for the independently made cPCI data acquisition board, the thesis focuses on how to program to implement the PCI device's driver using the VxWorks. A summary of the designing flow for the PCI device driver has been made. Then there is a program implementation according to the specific chip PCI9656. The points needing attention for the driver designing in the VxWorks multitask environments has been discussed.Aiming at the condition of multi-boards when the system has been expanded, the thesis focuses on the interrupt handling mechanism of VxWorks, and makes a discussion of the hardware implementation of the interrupt handling combining the hardware environment of the subject research projects. Then there is a discussion of the architecture of the interrupt service routine designing for the real-time system. A basic scheme which can be followed for the program designing has been supplied. At last, there is a specific discussion of the implementation of multi-interrupts handling program, which is successively used in the data transferring in DMA mode on the hardware platform of the subject.Aiming at the implementation of the command communication between the master machine on industrial chassis and the control terminal on the PC, the thesis makes a study of the workflow of the stream socket, and analyses the network program method based on the client/sever of stream socket mode. A network communication architecture using double buffering queues has been builded. Then there is a study of the dynamic management of the elements in the double buffering queues and the implementation of the communication protocol. At last, the network command communication has been implemented on the basis of the work above.The innovation points of this thesis mainly include two parts as follows:As for the interrupt design, the traditional ISR are divided into a shorter ISR and an interrupt service task through the semaphore. So the response of the interrupt becomes much shorter and the function of the interrupt handling becomes more abundant.As for the network communication, the FIFO scheduling and the priority-based preemptive scheduling are combined reasonably using the double buffering queues. So the system costs can be cut off and the emergent task can still be responded in time.