This document describes the MODBUS over Serial Line protocol. MODBUS Serial Line protocol is a Master-Slave protocol. This protocol takes place at level 2 of the OSI model. A master-slave type system has one node (the master node) that issues exp

his document covers the low level communication details for modbus at the data level for RS232 and other serial interfaces.

介绍工业串口液晶显示触摸屏与人机界面组态软件HMImaker的开发指南，工业液晶显示触摸屏是一种包含TFT LCD显示屏、LCD控制器、触摸屏、人机界面组态软件系统和单片机TTL电平串口，RS232，RS485，以太网等通讯接口于一体的嵌入式智能显示终端。工业串口液晶显示触摸屏技术开发是基于嵌入式控制系统采用FPGA纯硬件驱动显示，无任何操作系统，零启动时间，上电即刻运行，速度和可靠性领先于其他方案。系统配套自主研发设计的，具有知识产权保护的人机界面组态软件HMImaker设计界面，可“所见即所

MODBUS协议时总线通信的一种最常用的协议，支持rs485、rs232等通信方式-A time-MODBUS bus communication protocol most commonly used protocol, support rs485, rs232 and other communication