四通道隔离CAN通讯模块设计

Design of Four-Channel Isolated CAN Communication Module

摘要:

针对CAN总线通讯系统对实时性和可靠性的要求，本文设计了一种基于CPCI总线的四通道隔离CAN总线通讯模块。该模块与现有的同类CAN总线设备相比，在成本和电路集成度上具有明显的优势。该模块在硬件上采用了单片FPGA来实现CPCI接口以及四个独立的CAN控制器逻辑，并且使用了四个隔离的CAN收发器CTM1051同时实现电平转换与电气隔离；在固件设计中，分别采用PCI总线IP核和CAN总线IP核来实现PCI接口和CAN总线控制器；在软件设计中，按照模块技术要求来设计设备驱动程序、仪器驱动程序和软面板。经实验测试表明，该模块的位宽容忍度范围为±5%、采样点特征值为75%并能连续正常工作3小时以上，具有良好的性能指标和可靠的四通道数据收发功能。

Abstract:

In view of the real-time and reliability requirements of CAN bus communication system, this paper designs a four-channel isolated CAN bus communication module based on CPCI bus. Comparing with existing similar CAN bus device, the designed module has obvious advantages in cost and circuit integration. The module adopts a single FPGA chip to implement CPCI interface as well as four independent CAN controller logic, and uses four isolated CAN transceivers CTM1051 to achieve level conversion and electrical isolation at the same time. In the firmware design, PCI bus IP core and CAN IP core realize PCI interface and the CAN bus controller respectively. In addition, device drivers, instrument drivers and soft panel are designed as the module requirement. Through the experimental test, the module has a bit width tolerance range of ±5%, a sampling point characteristic value of 75%, and can work continuously for more than 3 hours. It has good performance index and reliable four-channel data receiving and sending functions.