Research And Development On The Embedded PLC Virtual Machine Of Numerical Control System

Open numerical control system is the research hotspot of NC technology now. With the development of the performance of high speed,high efficiency,high precision and intelligence,more and more functions which makes the software carry out all of the NC functions and minimize the scale of hardware are demanding.Machine logic,the kernel of the whole motion control,is necessarily realized through software too,which accelerates the development of SoftPLC. Embedded PLC virtual machine of numerical control system is researched and developed in this paper. At the beginning of SoftPLC developing system,users work out the ladder diagram and convert it into intermediate file by the compiler of Icomac-PLC development tool,then the intermediate code can be converted into assembler and be compiled,linked in order to generate machine code.Finally,execute the machine code in PLC simulation running system and get the right result so that implement PLC function.The main research work is as follows: (1) Thransfer ladder diagram into intermediate code. (2) Thrnsfer PLM file into assembler. (3) Compile the assembler into machine code so that generate PLE file in order to implement the execution mechanism of PLC virtual machine.In this way,the instruction execution speed of PLC is greatly increased and we can save much memory. (4) Execute machine code in PLC virtual machine of WinCE OS.