Hardware Design And Implement Of The EtherCAT Coupler Module

In terms of industrial automation, the emergence of the traditional fieldbus has brought a deep revolution. Because of unmixing with each other between multiple buses, however, the data between different fieldbuses cannot transmit high-speed effectively and real-time transmission. There are strict boundaries between the network protocol, so people are encouraged to seek a new way and to focus on the Ethernet. Compared with the field bus, industrial Ethernets have many advantages for a fast transfer rate, strong openness, good compatibility, remote access and data accessibility. Industrial Ethernet is now widely used in various industrial fields.Ether CAT which was developed and designed by German BECKHOFF company is a kind of industrial Ethernet technologies with real-time and high-efficiency transmission. It has modified the standard Ethernet protocol, and is mainly used in the data link layer in the ISO/IEC 802.3 protocol. At the same time, it replaces the TCP/IP protocol of the Ethernet network layer and transport layer with specific protocols, and then a kind of fast speed and good real-time industrial Ethernets can be achieved. Therefore it is very important to research the Ether CAT technology, which will enhance the level of industrial automation in China.This paper studies the characteristics of Ether CAT technology and the Ether CAT protocol under the background of the study on the development of PLC both domestic and overseas and the present situation, and under the research foundation of the understanding of the Ether CAT technology and learning to domestic chip processor. And it is proposed to develop a new goal of the domestication of PLC products using the domestic processor chip based on SPARC architecture and Ether CAT slaver controller ET1100 through the survey of PLC operation ability both domestic and overseas.First, an introduction of the development and research background of industrial Ethernet technology and PLC industry in the current world is made in this paper, and the status quo of the development and application of several representative industrial Ethernet is given.Second, a brief analysis of Ether CAT technology is given.Which include the characteristics of Ether CAT technology and Ether CAT frame data processing, the analysis of Ether CAT protocol and communications and data handling of the slaver system.Third, the paper introduces the physical and logical function of Ether CAT system, the design of Ether CAT slaver system, as well as the hardware design thought of Ether CAT slaver coupler module.Then, an introduction of hardware implementation of Ether CAT coupler module, including the design principle of each main part of the module, chip selection and working condition. Focus on the CPU peripheral circuit, configuration of the Ether CAT slaver control chip ET1100, the design thought of the circuit and the design of the PHY and RJ45 front-end ports.So as to the design thought to implement the converting Ether CAT 100 base- TX signal to an Ether CAT LVDS signal have completed.Finally, a simple test about the Ether CAT coupler module was taken, which consisted of two parts, the one board test of CPU of the coupler module test by SPE and a test about communication from the master to the slaver of the whole PLC system by a configuration software called Twin CAT of BECKHOFF.The final test results show that the hardware design of the Ether CAT coupler module meet the design requirements.