串口是计算机上一种非常通用设备通信的协议.大多数计算机包含两个基于RS232的串口。串口同时也是仪器仪表设备通用的通信协议；很多GPIB兼容的设备也带有RS-232口。这里简单的介绍 RS-232 RS-422 RS-485.-A serial port is a very general computer equipment communication agreement. Most computer contains two RS232 serial port based on. A serial port is also instrumentation equipment general communication protocol　Many GPIB compatible devices with RS 232 also mouth. Here simply introduced RS 232 RS 422 RS-485.