Data Communication Based On The Pci Bus Interface Card

With the growing requirements of weapon field experiment for measuring and controlling equipment, it turns into an urgent project to improve the performance of photoelectric theodolites. As the data communication system of theodolite demands strictly for a large quantity of peripheral devices in the performance of high data transfer speed, low transfer delay, high system integration and system maintainability, the paper discusses systematically data communication interface of the theodolite, and integrates the data communication module into the PCI board. Furthermore, PC-104, as an independent unit, processes data by itself.As a result,the data communication system with PC-104 module takes the disadvantage of low transfer efficiency, tough maintenance. Giving the problems above, the paper integrates the data combining and scattering system of PC-104 module in a single card interfacing to the master system. It has increased the data transfer speed, with low transfer delay, and improved system integration and modularization. In the paper, the interface between data transfer card and industrial computer adopts PCI bus interface, which is the critical part in the data communication system. The thesis selects VHDL as function description, with FPGA as the main hardware media, and implements the PCI bus interface. Although it is complicated to use FPGA, based on the data communication system, it not only makes the system upgrading much easier, and increases system integration simutaneously. The paper presents the design of the whole module and it's submodules respectively. The emulating result of EDA software is also demonstrated in the paper. Based on the design and the analysis above, The author made the hardware of the PCI bus interface card, and developed the correspondent software of drivers and applications.