Modbus 通讯协议，可以应用在触摸屏与PLC之间通讯，232与485都可以通用。-Modbus communication protocol can be used to communicate between the touch screen and PLC, 232 and 485 can be common.

基于STM32F103C8T6单片机的串口485通讯(MODBUS协议)实现多块板子间的开关量采集与控制采集-Based on STM32F103C8T6 single-chip serial communication 485 (MODBUS protocol) to achieve a number of boards between the switch acquisition and control acquisition