基于虚拟仪器的测控网络教学实验系统

The Design of Teaching Experimental System about Measurement & Control Network based on Virtual Instrument

本文设计了一种基于虚拟仪器的测控网络教学实验系统。实验系统采用上、下位机的基本结构,上位机由PC机构成,下位机由多个单片机节点构成。通过RS232-CAN/485通信控制器实现上位机和下位机节点的通信。上位机程序采用LabView图形化编程语言编写,其主要功能是实现命令发送并接收、显示、处理和存储下位机节点上传的现场数据和状态信息。下位机软件采用汇编语言编写,能实现模拟数据采集、模拟电压输出、数字量输出/输入、液晶数字显示等基本功能。在不改变硬件的情况下,通过更换不同的软件代码便可轻松实现RS232、EIA485和CAN等不同的通信功能。

A measurement ＆ control network experimental system applied to teaching based on virtual instrument technique is designed. The experimental system adopts basic framework of one master and multi-slaves. The host node is made up of the PC, and some single chip computer nodes consist of slaves, which can communicate with host computer by RS232-CAN/485 converter module. The host node is programmed by LABVIEW software, its main functions are to transmit the command, accept, display and store the data and state information from slave nodes. The slave nodes are programmed by assembiy language and can realize RS232,EIA485 or CAN communication and I/O operations only with different software codes and without any changes of hardware.