Design And Implementation Of E1 Interface Card And Drivers Of SIPG Gateway

In the VoIP system based on SIP, the SIP/PSTN gateway equipment is used for signaling and media conversion between IP network and public switched telephone network (PSTN). The SIP/PSTN gateway of traditional architecture, which is generally implemented with"RISC CPU+DSP", costs too much in development, but the SIPG gateway was implemented with general processor and software, which cuts down the cost effectively and facilitates expansion.The SIPG gateway is composed of the interface hardware-E1 interface card connecting the two networks, drivers and application software. As the basis of SIPG gateway, the E1 interface card connects the SIPG gateway equipments on Physical layer, and realizes the send and receive of E1 signal and the map to PCI interface, and also provides E1 interface of PSTN. Drivers of SIPG gateway takes charge of the initialization and console of E1 interface card, and provides the interface for the gateway software above.This paper introduces the design and implementation of E1 interface card and drivers of SIPG gateway. In the first chapter the design project, technical background and the system design is introduced. In chapter 2, SIPG gateway E1 interface card is designed at first; Then the implementation of FPGA logical function and configuration mode choice of FPGA are finished; And finally PCI interface and DS21Q354 interface are designed and implemented. In chapter 3, the design of SIPG gateway E1 interface card drivers is described in detail, which is developed on Linux. Several main functions are designed and implemented at first; Then several modules are designed; At last, the interface between drivers and the program of user space is realized. Finally, in chapter 4, a test for SIPG gateway drivers is reported. It can be seen that the design project of E1 interface card and drivers of SIPG gateway is feasible.