Development Of Cable Test System Based On CAN Bus

The cable is one of the important components of the electronic equipment.Its quality directly affects the overall performance and reliability of the system.The cable fault is one of the main reasons for the failure of the large system.But the current domestic market,less types of cable testing equipment,and the general testing equipment's function is not strong.Therefore,it is of great significance to develop a cable detection equipment with high integration,automation,high intelligence,high test coverage and high test precision.It is of great significance to improve the detection efficiency and detection accuracy of large cable network.This article has extensively consulted domestic and foreign literature,and has carried on the thorough research to the test principle.,has developed a cable test system based on CAN bus,which can realize short-circuit,open circuit,on-resistance,insulation resistance and resistance to cable Electrical strength fault detection.The system uses a modular design with 384 test points of the test capacity,and has fast test speed and high test accuracy.System man-machine interface is good,easy to operate,easy to expand.Test system hardware implementation Freescale MC9S12 X series of single-chip as the main control CPU,using modular structure,including the channel switching,function selection,conduction test,insulation test,electrical strength test and other modules.The relay matrix is designed to implement the test channel switching and test function selection.Relying on the chip's rich resources to design the excitation voltage generation,constant current source,voltage signal amplification,voltage signal acquisition,drive control and overcurrent protection and other circuits to achieve the test function.The software uses Microsoft Visual Studio 2010 development tools,using VC ++ object-oriented image programming to complete the system interface,parameter settings and the design of the test module to build a fast and convenient,good clear,easy to operate the host computer software.With Excel tools,to achieve the test process records,access and analysis.And the system uses Codewarrior as the software development environment,and C language prepared the underlying microcontroller software,to achieve the CAN bus communication function and test process control.Finally,after hardware debugging,build a hardware platform.The test results are compared with the functional requirements and technical requirements.The comparison shows that the test system has realized the functions stipulated in the functional requirements and satisfies the technical indexes,achieve the desired design results.