Design And Implementation Of Key Modules In TTE End System

Since its inception,Ethernet has maintained a rapid development.It has been widely used in office systems and other industries.It has accumulated a large number of user bases and a wide range of application bases,and its transmission bandwidth has increased by an order of magnitude.However,the use of event triggering mechanism to transmit data,and the use of carrier-sense multiple access/collision detection method to resolve conflicts in Ethernet,resulting in its real-time and deteministic data transmission cannot be guaranteed in critical applications.Because of its high bandwidth,real-time performance,deteminism,and compatibility with traditional Ethernet equipment,TTE makes up for the shortcomings of traditional Ethernet and is receiving increasing attention.It will be widely used in the field of areospace,automotive manufacturing and industrial control.TTE is based on Ethernet technology and adds time triggering and time synchronization services to handle time-triggered services that require high real-time performance,and can handle both rate-limited and ordinary Ethernet services.The TTE network is mainly composed of a TTE end system and a TTE switch.The TTE end system serves as a network core device and mainly performs functions such as data transmission and reception,and network clock synchronization.This article will focus on the design and implementation of the TTE end system.This thesis is based on the laboratory project "Time-Triggered Ethernet End System Collaborative Development".In accordance with special design requirements of the project,this articl firstly introduced the research background and the current research status of time-triggered Ethernet at home and abroad.Secondly,the overall design of the TTE end system is given and the functions of each module are described.Thirdly,the design and impementation of three key modules in the TTE end system are introduced,including the design and imlementation of the transmit processing module,the receive processing modlue,and the PCIe bus interface module.The transmit processing module mainly completes packet processing,queue management,sending scheduling and sending redundant processing,including 128 TT services,128 RC services and BE service.The receive processing module mainly completes service's integrity check,receive redundant management,store control and receive window check of TT service,and it also deals with 128 TT services,128 RC services and BE service.The PCIe bus interface module is used to implement the physical layer,data link layer and transaction layer protocol of the PCIe bus,mainly including TLP parsing and encapsulation,out-of-order processing of read completion packets and interrupt control and so on,to ensure the normal communication between the computer and the board.Finally,functional simulation and board-level testing are conducted on the three key modules of the TTE end system.Meanwhile,debugging problems encountered are analyzed and summarized.The test results show that the scheme described in this paper can handle time-triggered services,rate-limited services,and common Ethernet services at the same time and meet the performance requirements.