| The digital integrated circuit is applied widely now in the world. Benefits in digital integrated circuit's swift development, the performance of the Digital SPC Exchange have been greatly improved, while it's cost largely drops, so as to the middle and small Digital SPC Exchange can be popularized, the capacity of which is dozens to several hundreds telephones. The hotel and service industry is developing rapidly In recent years, it provides a broad market space to Digital SPC Exchange.The completion of exchange the voice data according to the communication process is the precondition and foundation to realize all kinds of extended functions. At present, the special voice exchange chip is adopted in many Digital SPC Exchanges. It makes the research and development process becomes simple, but it limits the capacity and function of the Digital SPC Exchange, and the expansibility is not very good either. Because the enterprise's size varies, the research and development enterprises of Digital SPC Exchange expect a system platform design which is more flexible and easy to expand to satisfy the demand of market in diversified sizes.According to the requirement of this project, this thesis use FPGA, instead of special switch chip, to complete the work of voice exchange. This thesis emphatically introduces the module partition inside the FPGA on control board and the how to design these modules, It mainly includes data collection module, interface state detection module, design of interface between FPGA and CPU&DSP, voice exchange module. It also gives a detailed description of how to complete voice exchange according to the communication process and implement the extended functions by FPGA, embedded software and DSP.The prototype of Digital SPC Exchange, which is designed according to this thesis, has been test strictly on performance and stability, and is ready for production. |
