【摘要】 基于开发系统中设计好的梯形图程序需要下载到下位机中解析并运行,软PLC工作系统的工作性能取决于运行系统能否高效准确地解释执行梯形图程序的目的,通过比较解释型PLC和编译型PLC的特点,采用了一种解释型PLC高效执行方法,并研究了上位机下载的通信帧解释方法,反向转化为指令表的思路,通过转化后的指令表进行梯形图程序网络连接信息的提取、梯形图各图元的解释执行,以及各梯形图功能单元的算法实现。对堆栈的实现方法及软中断的实现方法进行了特别研究,在STM32的ARM平台上进行的算法验证得出,该方法能高效地解析梯形图程序,只需要一个机器指令周期就可以进入梯形图程序解释接口。更多还原

【Abstract】 The ladder program designed based on the development system needs to be downloaded to the lower computer for analysis and operation. The working performance of the soft PLC working system depends on whether the operating system can effectively and accurately explain the purpose of executing the ladder program. By comparing the characteristics of interpretive PLC and compiled PLC,an efficient execution method of interpretive PLC is adopted. This paper also studies the interpretation method of communication frame downloaded by the host computer,and reversely transforms it into the idea of instruction list. Through the transformed instruction list,the network connection information of ladder program is extracted,the interpretation and execution of each element of ladder diagram,and the algorithm implementation of each ladder function unit. The algorithm is verified on ARM platform of STM32. It is concluded that this method can parse ladder program efficiently,and it only needs one machine instruction cycle to enter ladder program interpretation interface.更多还原