The Research Of Missile-embedded Computer Real-time Test System

The performance of missile-embedded computer is directly related to whether themissile can hit the target. So the missile-embedded computer testing is very important.At present, the bus standards are not uniform in the test system. So the systemintegration is difficult. Besides transmission rates and real-time of the system cannotachieve the demand of high-precision test. To solve the problems above, the Ethernet isintroduced to build a distributed network real-time test system. Data’s transmission oftraditional Ethernet is uncertain, and the real-time performance of the system is difficultto guarantee. In order to build a missile-embedded computer real-time test system, theReal-time Industrial Ethernet fieldbus EtherCAT is employed as the test bus of thesystem.Firstly, in this paper, after doing the research of the performance of EtherCATindustrial Ethernet and the communication mechanism, The EtherCAT has someadvantages, such as flexible topology, simple system configuration, good real-timeperformance, high efficient and high-speed of data communication. Because EtherCATaddressing and synchronization methods are used, the process data of different devicesare gathered in an Ethernet frame. It is easy to read and insert data to the Ethernet frame.The distribution clock is adopted for all test modules working in the same timeline, sothe distribution clock provides a time reference for the synchronous sampling andoversampling.Secondly, the German Beckhoff test modules are put use to build the real-time testsystem. When the system is accomplished, it can accept high synchronization accuracy,and it can achieve the real-time test of the digital input and output, DA output andRS232signal on missile-embedded computer. The test modules of the real-time testsystem are scanned and configured through the TwinCAT software system. Meanwhile,the control procedures of all test modules are designed. The interface of test modulesand system are defined according to TwinCAT ADS interface tool TcAdsDll. Thanks toC++Builder, the machine interface of the test system and test programs are coded toachieve real-time read and display data collected from each test module.Finally, the hardware and software in the missile-embedded computer real-time testsystem are debugged. After the Clock synchronization accuracy test, synchronoussampling test and RS232serial communication test by the system, the data of test modules are shown on the machine interface. Further more, the communication dataframe grabbed by NetANALYZER board from Hilscher are analyzed. In a word, theperformance of the test system is excellent. It can reach the real-time test requirementsof high clock synchronization accuracy, synchronous sampling and serialcommunication without loss of data.