杨胜利 李超 余亮

摘 要： 基于IP核的SpaceWire?PCI通信卡进行通信时，没有考虑传输过程内相位失真问题，其通信效果存在实时性能低、抗干扰性差和通用性低的缺点。据此设计基于FPGA的嵌入式通信系统的通信卡，其整体架构由FPGA模块、以太网88E1111 PHY芯片、MCP2515 CAN控制器等组成。采用FIR滤波器分布式算法处理通信卡信号传输时的内相位失真问题。利用SoPC系统的Nios Ⅱ集成开发环境设计通信卡软件：设计初始化程序实现FPGA模块中Cyclone Ⅲ 3C25F32芯片控制寄存器的配置；设计通信程序实现通信卡中数据信息的发送和接收。实验证明，所设计通信卡通信效果具有实时性高，抗干扰性好及通用性高等优势，能够极大地提高通信效率。

关键词： FPGA； 嵌入式系统； 通信卡； 接口电路； 控制寄存器； 通信程序

中图分类号： TN914?34； TP274 文献标识码： A 文章编号： 1004?373X（2018）22?0088?04

Abstract： The SpaceWire?PCI communication card based on the IP core has the disadvantages of low real?time performance， poor anti?interference and low universality in communication effect because the internal phase distortion problem in the transmission process is not considered. Therefore， a communication card based on FPGA is designed for the embedded communication system. The overall architecture of the communication card is composed of the FPGA module， Ethernet 88E1111 PHY chip， MCP2515 CAN controller and so on. The FIR filter distributed algorithm is adopted to deal with the internal phase distortion problem during the signal transmission of the communication card. The Nios Ⅱ integrated development environment of the SoPC system is utilized to design the software of the communication card. The initialization program is designed to realize the control register configuration of the Cyclone Ⅲ 3C25F32 chip in the FPGA module. The communication program is designed to realize transmitting and receiving of data information in the communication card. The experimental results show that the designed communication card has the advantages of high real?time performance， good anti?interference and high universality in communication effect， which can greatly improve the communication efficiency.

Keywords： FPGA； embedded system； communication card； interface circuit； control register； communication program

0 引 言

目前，半导体技术日益成熟，研究开发大范围可编程逻辑器件成为电子系统开发领域内的主要研究目标。在大范围可编程逻辑器件中FPGA最具代表性[1]，随着嵌入式系统与网络结合的日益加深，其已渐渐成为未来的发展趋势。人们能够利用嵌入式系统通过网络对家庭及工作、学习等不同环境中的状态进行远程查看。因此，嵌入式通信系统在未来对人们的影响更为深远[2]。传统基于IP核的SpaceWire?PCI通信卡进行通信过程中，没有考慮传输过程内相位失真问题，其通信效果存在实时性能低、抗干扰性差和通用性低等问题，已经不能满足人们的需求[3]。本文设计基于 FPGA的嵌入式通信系统通信卡提高通信系统的通信效率和抗干扰性。……