PC开放型数控系统ModBus接口的研究与实现

摘要

为提高PC数控系统的开放性和可扩展性,针对系统的低速外设,提出使用具有软硬件接口标准支持的ModBus 总线实现与PC数控系统互联的接口设计方法.论述系统ModBus接口的软硬件结构；分析接口实现中的弱实时性要求和多任务线程间的数据共享问题.通过某PC数控系统外扩展主轴变频器和PLC验证了该接口设计的可行性和正确性.%To improve the openness and expansibility of CNC system based on PC, with regard to its peripheral equipments of low speed, an interface design between peripheral equipments and CNC system was present using ModBus with supports of hardware and software standards. The hardware and software structures of ModBus interface were discussed. As to implementation of interface, Low-strictly real time requirement and data sharing between functional threads were analyzed. Feasibility and validity of interface design was proved though attaching transducer and PLC on a CNC system based on PC.