The Design Of PROFIBUS DP Slave Based On FPGA

Great changes have taken place in the industry control since the fieldbus technologies came forth. The mode of the industry control changes from centralized to distributed, and the data exchange mode changes from slow parallel to high-speed serial. All the changes above make the industry control be able to achieve networking management. Among the fieldbus technologies, PROFIBUS DP is representative for its high speed and reliability, and holds a large share of national market in the industry control field.According to the demand for real-time control of masses of distributed I/O points, a kind of PROFIBUS DP slave based on a popular digital circuit design device called FPGA is designed in this paper. In the DP slave, the dedicated PROFIBUS DP protocol chip SPC3 is used to explain the DP format telegram; the CycloneII device is applied in the transform of the slave's statemachine and the controlling of slave's I/O data. The DP slave can exchange the data with the DP master periodically and has been expanded the serial communication interface with the personal computer. Taking advantage of the serial communication interface, the users can monitor the data in-out the slave's I/O and modify the configuration information of the SPC3 chip.This paper focuses on the contents of the DPV0 profile of the PROFIBUS DP and the realization of the DP slave's hardware and software. According to the Top-Down principle, all of the function models in the FPGA device are designed based on the hardware structure and slave's function. After passing the function and timming simulation tests by the ModelSim and QuartusII, all the models are loaded down to the FPGA device. At last, kinds of tests, including statemachine transform flow, different baud rates on DP bus and stability factor, are carried out to verify the feasibility of the DP slave designed in this paper.