串行通信接口 RS-232 和 RS-485 是在任何时候都常用的接口。它们不仅已经被内置于每台PC,而且已被内置于从微控制器到主机的多种类型的电脑和与它们连接的设备-RS-232 serial communication interface and RS-485 is used at all times of the interface. They have been built not only in each PC, but has been built from the microcontroller to the host computer and a plurality of types of equipment connected to them