Design And Development Of Programmable Automation Controller Based On ARM And Linux

PLC,a combination of computer and relay control technology,has been widely used in theindustrial automation system.However,at present20%of the high-end applications is beyond the PLCfunctions traditional one can provide for the closed structure of software and hardware both indevelopment system and running system and other defects.While programmable automationcontroller(PAC)can meet the20%high-end applications for openness and flexibility,algorithm andnetwork communication,together with the stability and reliability.To develop the PAC system iscrucial to the entire industrial control automation.In this paper,the PAC’s development system and running system and other technologies relatedare introduced first,and the feasibility of applying ARM and Linux technology to the development ofPAC is studied.Then the characteristics and working principles of PAC’s running system isstudied.Combined with the hardware and system software architecture and working mode of PAC,theI/O interface,operating system and GUI is determined.Finally,based on the hierarchical model of PACdevelopment,using the"ARM+Linux platform"software and hardware architecture,its software isdivided into four relatively independent part: hardware abstraction layer,driver layer and GUIlayer,and an open embedding programmable automation controller development platform is achieved.In the developed PAC system,an I/O interface board is made with the mini2440board.UsingLinux as the operating system,Qt as the GUI and under the Fedora environment,soft PLCregisters,instruction set and scan logic,the touch screen UI and SQLite database are designed.Easilysupporting the C language mixed with the ladder instruction,the PAC system would shorten thedevelopment cycle of control system,and can meet the requirements of industrial site by practice test.