针对RS485总线不定数量的从站即插即用的难题,本文以光电模组检测需求为例,提出一种基于单片机设备唯一标识符的RS485总线即插即用的软件控制方法。该方法无需改动硬件电路即可实现RS485总线上的从站数量扫描、从站地址自动分配和从站热拔插检测等功能,并通过实验验证了该方法的有效性和灵活性,从面满足了使用者对从站任意拔插的需求。

With regard to the plug-and-play problems of the uncertain number of slave stations on RS485 bus,taking the detection requirements of photoelectric modules as an example,a plug-and-play software control method of RS485 bus based on the unique identifier of single chip microcomputer equipment is proposed in the paper.Without changing the hardware circuit,through this method,functions including scanning the number of slave stations,automatically distributing the addresses of slave stations and hot plug detecting for slave stations in the RS485 buses can all be realized.In addition,the effectiveness and flexibility of this method can be proved by experimental data,which solves the problems of user’s demand for arbitrary plugging of the slave stations.