Design And Implementation Of Digital Switching Chip Based On FPGA

The digital switching chip is a key device in the program-controlled digital switch.However,China's digital switching chips mainly rely on imports from abroad.With the passage of time,They will face the risk of suspension of production or supply from foreign manufacturers,and will also require changes in technical indicators as the needs of domestic users change.It is difficult to rely on imports from abroad in a timely manner Meet domestic needs.Based on the study of the principle of digital switching,this paper analyzes the function and structure of the digital switching chip,Furthermore,Discusses the working methods and working principles of T-type connectors and S-type connectors.According to the demand of dispatching communication program-controlled digital switches for digital switching networks,A digital switching network with 4096×4096 time slots was designed,The network uses a TST non-blocking structure.The primary T connector uses sequential writing to control the readout operation mode.The bus of each T con nector has 128 time slots,The S connector uses input control operation mode,The secondary T connector uses Control writing and sequential reading work mode.Because FPGA has the characteristics of self-designed circuit,According to the requirements of technical indicators,A digital switching ch ip is designed based on FPGA which can realize two working modes of"switching mode" and "message mode".The chip is based on the principle of digital switching network and mainly includes 4 modules including clock generation module,data sending module,data receiving module and microprocessor interface.The clock generation module mainly provides the working clock for the digital switching chip and generates various working clock;The data receiving module mainly receives sorts and stores the time slots above each bus;The data sending module mainly stores,sorts and sends the time slots after the time slots are exchanged;The microprocessor interface module is mainly responsible for the communication between the microprocessor and the digital switching chip,Moreover,the modules can be combined according to the working requirements of "exchange mode" and"message mode".The third-party tool Modelsim software was used to simulate the digital switching chip on the Quartus development platform provided by Altera.The simulation results show that the design can meet the technical requirements.Finally,the Cyclone IV EP4CE115F29 chip provided by Altera was used to burn the code of the digital switching chip into the chip for testing,Moreover,The signal inside the digital switching chip was captured using SignalTap ? and the logic analyzer included in the Quartus development platform.Test and analysis results show that the chip has realized the"switching mode" and "message mode" and meets the technical requirements.In the case of frame synchronization,it can achieve non-blocking switching of 4096×4096 time slots.