Research And Development Of Data Link Layer Protocol Of Foundation Fieldbus

Along with the technical developing of computer, micro-electronics and communication, signal transmitting method was developing from analog to digital in the field of process control and meanwhile people brought forward a new technology: Fieldbus. There are two main characters of Fieldbus: one is digital communication and intelligent process of field meters, and the other is that it's opening and available to everyone totally. From then on, Filedbus became the main technology in the field of process control system.FF H1 standard is the study object in this paper. This paper mainly focuses on communication mechanism, bandwidth allocation scheme, link management and scheduling mechanism of Data Link Layer. There still be the realization of communication card hardware and protocol stack software. Finally it established a demo system to accomplish the project.There are seven chapters in this paper. In chapter 2, this paper firstly introduces the system architecture of H1 protocol standard and reference model, then it briefly describes each layer. Secondly this paper detailed presents the design and realization of hardware and software of H1 communication card in chapter 3. It still puts forward some resolvent for three pivotal problems: MAU designing, memory copying and memory limitation.It is most important of conducting research on protocol standard of DLL in chapter 4 and 5. This paper concretely presents how to designing and developing algorithm and each software module of BASIC and LAS devices. It brings forward a creationary timer management mechanism in chapter 4. It still indicates the existent deficiency of communication mechanism and bandwidth allocation scheme, then puts forward some resolvent.In chapter 6, this paper gives methods to debug and test protocol stack software via established demo system. Finally in chapter 7, this paper summarizes all the previous work and gives some advices for subsequent work.