Design And Implementation Of Data Acquisition System Based On CPCI Bus

Because of the complex environment in the signal detection and feedback loop of industrial control process, also due to the large amount of data sampled and high requirements for the speed and accuracy of data acquisition, excellent performance of data acquisition system has great significance for making the process accurate, efficient and stable. With the development of computer bus technology, CPCI bus gradually becomes one of the most reliable buses of industrial personal computer(IPC) for its high-performance. CPCI bus not only ensures high-speed data transmission, but also has advantages of universal operating system and open architecture, which ensures perfect compatibility and reliability for the data acquisition system and makes it be widely applied.Now the data acquisition system based on CPCI bus has disadvantages of single function and poor scalability. This paper designs and implements a data acquisition system based on CPCI bus utilizing FPGA development technology of Xilinx. The hardware system has general design framework and is compatible with synchronization operation of different function modules. To be specific, the system consists of the master card for acquisition control based on CPCI bus and two functional sub card. The universal interface module is designed for the connection between the master card and sub cards, and it defines the hardware standard and communication protocol, which greatly improves the functional scalability of the system.The master card is responsible for the scheduling of system control and communication with IPC and peripherals. One of the sub cards is an SSI acquisition card supporting multi-channel SSI signal acquisition and command output control, the other is a DAC processing card which is capable of multiple controllable outputs of digital-to-analog conversion. The hardware and interactive software constitute the data acquisition system. After the hardware design and communication test, the data acquisition system takes performance tests in the motion control loop based on electric servo cylinder. Tests have shown that the data acquisition system based on CPCI bus can simultaneously achieve different data processing functions, meeting all specifications required and the system is efficient and stable.