Application of distributed I/O system based on Modbus/TCP protocol in  train simulator

WAN Le，QIAN Xuejun
（College of Electronics and Information  Engineering， Tongji University， Shanghai 201804， China）

Abstract： In order to solve the problem of real time data exchange between the humanmachine interface of train simulator console and train simulator host computer， a solution of the distributed I/O system based on Modbus/TCP was proposed, aiming at overcoming the disadvantages of the traditional I/O interface card such as the large bulk， high cost and difficult maintenanceFirstly  technical characteristics of Modbus/TCP protocol were introduced in detail After the analysis of the performance requirement of the system， X20 system of B & R was selected to establish the hardware system Based on the AS platform of B & R and made use of C programming language， the software was programmed Finally， the distributed I/O system was applied to the train simulator of Shanghai Metro Line 7 The results indicate that the system is stable，reliable and well compatible， and it meets the realtime performance requirement The system can be applied to the other train simulator directly
Key words：  train simulator; distributed I/O; Modbus/TCP