Design Of Ethernet Interface For The PAC In The New Controller

PLC as an industrial controller has good stability, powerful, high reliability advantages,long active in the field of industrial automaion control the main battlefield. But with thetechnology development highlights the presence of hardware architecture are not mutuallycompatible operating system using special-purpose programming languages and commandsystem of different manufacturers vary; PC, the controller has a good open, rich sharedresources, but the reliability, stability in harsh environments, real-time is difficult to achieveindustrial standard of occasions. Pressing the industrial application of a new type ofprogrammable automation controller (Programmable Automation Controller, PAC) came intobeing. PAC combines the advantages of the advanced software features of the PLC reliabilitywith a PC, so it has good openness and reliable, durable, stable, real-time and other industrialproperties.Our laboratory development team has developed a new controller PAC, but as anindustrial controller, PAC also required to have a strong network communication ability, has arich communication interface. This article focuses on how for the the PAC design of Ethernetand other communication interfaces based on the platform, so that PAC down by thecollection site information of various types of communication interfaces for RS-232, CANBus, ZigBee wireless communication with multiple io, PLC connection, constitute theunderlying network; via the Ethernet interface, the PAC can constitute a distributed controlnetwork at the same level, synthetic industrial PC unit up a relatively complete industrialautomation and control systems, and ability to integration and information network.If the Ethernet interface hardware circuit design of reliability in order to ensure that thedesign of the Ethernet interface quality hardware applications in industrial environments;given Ethernet interface of the software design underlying driver under Linux to achieve thedesign process as well as UDP/IP protocol stack implementation, especially Ethernet networkoptimization optimization ideas and measures. In order to access the PAC the underlyingcommunication interface RS-232, CAN, wireless ZigBee Ethernet, also uses UDP waydesigned the incompatible network abstraction layer high-level protocol conversion program,the conversion PAC platform as a server listen for the PC as a client, in order to achieve thedata communication between non-IP devices and IP devices.By Ethernet communication interface system design of the PAC, the PAC control systemflexibility, openness, and overall performance has been significantly improved, the Practicehas proved that this broad PAC Ethernet interface technology has good application value.