The Design And Implement Of A Ethernet And Multi-CAN Bus Gateway

Field-bus Control System is often consisted by filed devices, filed bus, computer interfaces, and communication devices. The communication between devices in filed is done by the filed bus, which can be used in process automation, make automation, building automation, family automation and so. So Filed-bus becomes very important and active. In the filed-buses, the first one certificated by the international organization for standardization is the CAN (CAN: Control Area Network) bus. Although the CAN bus has done excellently, it can directly connected to Ethernet. So the information can only follow in the local network, can not be shared by the remote user. It doesn't contribute to the development of factory automation. If CAN bus can work together with the Ethernet well, the field control, the produce adjustment, the enterprise management and so on can get more convenient.Because of the above reasons, the paper designs a gateway of Ethernet and multiple CAN bus. It studies the protocol of CAN bus and Ethernet, interface technology of them, and communication technology between them. The LPC2294 used as the core processor of the gateway, DM9000 as the Ethernet controller, mcp2510 as CAN controller are the main devices in the gateway. The embedded OSμC/OS-Ⅱ, LWIP are used to implementation the system management and Ethernet communication.The Ethernet and multiple CAN bus gateway is designed successfully. The macro design, software and hardware design are talked in this paper, event how to port the LWIP to ARM7 andμC/OS-Ⅱand the driver of CAN controllers and DM9000 are introduced, too.