The Analysis Of DeviceNet Protocol And Development Of Embedded-based Slave

DeviceNet protocol is designed for factory automation，it is an open field busstandard CAN bus. With the rapid development of field bus technology, DeviceNetfieldbus technology has also been an unprecedented development. Compared to otherbus, DeviceNet has its own advantages, its stability, real-time and high efficiencymake it greater room for development.This paper is devoted analysis DeviceNet protocol and design of DeviceNet slave.The main studying work is shown as follows:(1)Analysis DeviceNet network protocol specification. DeviceNet protocol isdeveloped by OVDA organization. It is one of international standard fieldbus.Analysis of DeviceNet network protocol specification is the theoretical basis fordevelopment of DeviceNet Slave protocol analysis. This paper analyzes and researchDeviceNet network operating system and service processes. DeviceNet networkservice process includes five steps: a system power, establishing a connection,resource allocation, network services and offline management.(2) The overall design of DeviceNet slave. The overall design includes hardwaredesign and software design. Hardware section: Firstly we should determine hardwaresolutions according to demand; then select the controller and peripheral chips; Finally,divide the system hardware systems, and hardware system consists of power supplycircuits, communication circuits, I/O circuit. Software section: Firstly we shoulddetermine software solutions according to demand; Then, Design the overall structureof software. Software system includes initialization module, message production andconsumption module, automatic baud rate detection module, interrupt handling moduleand so on. Finally, configure the programming environment.(3) Build a DeviceNet network test platform. DeviceNet network test platform includes USBCAN-ED DeviceNet master, USBCAN analyzer, DeviceNet slave and soon. USBCAN analyzer access to the DeviceNet network. It can capture packets whichtransmitted between master and slave on the network in real time. And analysis thepacket format and meaning in-depth. Thus,We developes a DeviceNet Slave. It fullymeets the design requirements.