Design Of The Low-power CAN Controller Based On BOSCH CAN2.0B Protocal

Controller Area Network is called CAN for short. The outstanding features such as the high-speed baudrate and reliablity, the convenient connection with the bus, multiple master nodes, brief protocal and high cost-effectiveness is that why CAN bus can be one of the most popular Field-bus. The high bit rate, high EMI quality and the coverage of all error are its basic requirement. The intention of the CAN 2.0B protocal is realizing the function of Data Link layer defined by ISO. Its main function includes receiving bit stream from can-bus and organizing it in the frame format. In the meantime the controller processes the frame filtering and and detect the error occurred in the can-bus. The CAN controller also can bread down a frame and send it onto the can-bus in the bit stream format and at the same time arbitrate the bus and detect the error in the can-bus.The CAN controller is designed in the top-down way and its function and timing can be guaranteed by the back-end tools and FPGA verification. The paper begins with the analysis of CAN 2.0B protocal and partition of the CAN-bus controller system according it function. Later charpter introduce the design of the submodule. The paper adopt a method suitable for the bus controller to resolve the conflict of reading operation to registers and the internal modify of the value of register. This method is according to the principle of the multiple clock domain. Also the novel pipeline filtering method is put forward to increase the system frequency. The back-end tool Power Compiler is used to reduced the power comsumption and this is also the innovation.The function simulation and back-end simulation of each module is executed in Modelsim SE 6.1. The result of simulation indicates it can work well. The CAN controller is implemented in 1st Silicon 0.18-μm CMOS technology. Now the CAN controller is used in Myson technology CS8959 project.