Development Of Data Packet Encoding And Decoding Software Based On The User Interface Protocol

When the test system is built based on the Joint Test Architecture(JTA),a large number of test equipments need to be connected to the Joint Test Platform(H-JTP).Most of the test equipments have information interface,and they communicate with the external system through the user interface protocol.The mismatch between the user interface protocol and the standard object model adopted by JTA leads to the failure of these test equipments to communicate directly with H-JTP.To solve the above problems,this paper develops a set of universal user interface protocol codec tools including Universal Protocol Template Editing Software,Protocol Encoding Software,Protocol Decoding Software and Protocol Information Display Software,It is important to improve the ability of rapid construction of large-scale joint test by supporting the free access of test equipment with information interface to H-JTP system.Firstly,according to the Interface Control Document(ICD)of several test equipment,the characteristics of user interface protocol based on common hardware interface are analyzed,including: containing base data type,string,array,bit data type;containing multiple processing functions;multiple nested;multiple branched;containing recurring data elements etc.a universal user interface protocol format that covers all of the above protocol features is designed on this basis.On the basis of the format of the universal user interface protocol,Universal User Interface Protocol Template Editing Software is developed,it supports the editing of user interface protocol templates containing the above complex features,it can also convert the user interface protocol in the Interface Control Document(ICD)into a program recognizable protocol template(xml file)that is used for protocol encoding and decoding software.The conversion technology of JTA object model and user interface protocol data packate are studied,the automatic conversion between the two is realized,it provide technical support for Protocol Encoding Software and Protocol Decoding Software.Protocol Encoding Software can convert the object model instance data to corresponding protocol data,while providing the visual protocol data editing interface for the users,It can package the protocol data from the object model or the protocol data edited by the user into protocol data packets,the data packets can be sent to external devices through corresponding hardware interfaces according to the timing or trigger mode set by the user.Users can also quickly generate device simulators using protocol encoding software to support the construction of a joint test system.Protocol Decoding Software can receive data packets and parse packets according to protocol template.Using protocol level management method to improve protocol matching efficiency;Using multithreading technology to improve protocol resolution efficiency;A cyclic queue storage protocol packet is used to avoid packet loss when the received data flow is uneven.Support the protocol data to be published on H-JTP platform as an object model or data stream.The final test results show that,The function and performance index of Universal Protocol Template Editing Software,Protocol Encoding Software and Protocol Decoding Software meet the requirements,and have good versatility.