Embedded PLC Programming Techniques of Forging CNC System

This paper implements embedded PLC programming control system for CNC forging equipment. The control system is based on Windows XP platform, using Visual Studio integrated development environment. The PC programming features include function block (FB), ladder diagram (LD) and instruction list (IL) language. And this paper elaborates the data structure of three kinds of programming languages and implements the loading process of program. After experimental verification, the control system realized the programming control system for users, and provided a good foundation for further explanation of the follow-up program.

Implementation of Transformation Module of Soft-PLC Based on MDI Application

This paper presents a method to achieve ladder diagram language conversion to the instruction list language based on VC multi-document application. The module by analyzing the difference between the series program and parallel program when the ladder diagram language transform into the instruction list language, and according to the special position of the element correction to arrive at a correct instruction list program. The advantage is that this method is simple and practical.

A Transformation Method between PLC Ladder Diagrams and Instruction Lists Using Recursive and Stack Algorithms

The method of transforming a ladder diagram (LD) and an instruction list (IL) of PLC (Programmable Logic Controller) to each other is investigated in this paper. Firstly, ladder-step is adopted on transforming LD into IL. Ladder-step is divided series or parallel by using recursive algorithm, and then complicated ladder-step can be divided into several simple ladder-steps which can be converted to IL easily. When obtaining simple ladder-steps’ IL, combining them together to get final IL program of complicated LD program. Secondly, on transforming IL into LD, stack algorithm contributes a lot. Scanning IL to generate LD of each instruction block, and then pushing them into stack. Combine LDs in the stack by operating instruction, and then IL is transformed into LD successfully. Finally, in the last part of this paper, we show our PLC software and lower position machine. In addition, this transforming algorithm has already applied in PLC software successfully.