Method and system for conversing trapezoidal pattern to be instruction catalogue program, and interpretation execution method and system

Abstract

The invention discloses a method and a system for converting a ladder diagram into an instruction list and carrying out the interpretive execution of an instruction list. The ladder diagram conversion method comprises the following steps: mapping the ladder diagram to an AOV diagram, establishing a binary tree representative of the logical relationship between the instructions based on the AOV diagram, and converting the ladder diagram to the instruction list by the postorder traversal of the binary tree. The method and the system perform the conversion between various complex ladder diagramsand instruction lists, particularly the conversion of the multi-output ladder diagram to the instruction list. Additionally, the converted instruction list exists in the form of postorder expression,which is conducive to increasing the efficiency of interpretive execution of the PLC master controller.

Description

technical field [0001] The invention relates to a method and system for converting a ladder diagram into an instruction list program and explaining and executing the instruction list. Background technique [0002] Ladder diagram and instruction list are commonly used programming languages ​​for programmable logic controllers (Programmable Logic Controller, PLC). The ladder diagram language originated from relay logic and execution line diagrams. Different icons are used to represent different instructions, and concepts such as series and parallel are used to organize the sequential positions of icons to express control logic. The ladder diagram is intuitive and echoes the electrical control schematic diagram, but it is non-executable code for PLC and cannot be run directly. The instruction table is a series of self-defined instruction sets that conform to the IEC61131-3 standard, similar to assembly language. Each instruction is composed of opcode and operand, and the prog...

AI Technical Summary

Problems solved by technology

[0005] This method is the same as the existing known conversion scheme, only applicable to the conversion from the ladder diagram containing single output to the instruction list, and its weak point is that there is no mention of how to convert the ladder diagram program to the instruction list containing multiple outputs, And for some ladder diagrams with complex series-parallel logic relations, the conversion results cannot be obtained very well, that is, it is not suitable for ladder diagram programs with relatively complicated series-parallel logic relations

Images