Research Of Embedded And Reconfigurable CNC System Based On MC68K And FPGA

The traditional CNC system mostly has a special and close structure, which can provide the users very limited choices, and the users can't modify the functions of the existing CNC equipments to meet their special requirements. Different manufacturers provide different manipulations to the users, and the users have to spend a lot of time and money on staff training and maintenance of equipment. All the problems referred above seriously hampered the CNC manufacturers and system integration persons and the users to adopt fast and creative methods to solve problems of NC and system integration in the manufacturing process. With the development of electronic technology and computer technology, CNC technology is developing forward flexibility, intelligence and Internet-opened pattern. According to the existed problems and development trend of CNC system, this paper aims to establish an open-architecture CNC platform fitted for field machining characters, which makes the system flexible features with reconfigurable hardware and software. And meanwhile, the functions of monitor and diagnose and network are introduced to this framework to meet the requirements of intelligence and network.This paper introduces reconfigurable design methods and chooses specific platform of hardware and software to research and develop the embedded and reconfigurable NC system based on in-depth study on technology of embedded system. The hardware is based on the MOTOROLA's high performance, 32-bit embedded MPU MC68F375 and ALTERA's FPGA(Field Programmable Gates Array), and it is also equipped with the required peripheral modules to extend itself to a whole hardware system. The software is based on the excellent-performance, embedded RTOS(real-time operating system) VxWorks, and the application software is required to be developed to turn VxWorks into a practical embedded NC system, which not only has virtues of high reliability, high performance, but also can be transplanted and trimmed so well as to modify and reconfigure the functions conveniently according to system requirement.The following are the main research contents of this paper:(1)The paper deeply researches on the hardware design of mainboard which is based on high performance MPU MC68F375, and so are the modules of storage, data acquisition, communications and networks.(2) The paper deeply researches on the serial configuration and reconfigurable design methods based on FPGA, and many crucial interface modules are designed on the basis of FPGA such as motor control, input/output control of the machine tool, keyboard array, LCD display control.(3) The paper deeply researches on the transplant of the embedded RTOS VxWorks into the hardware platform and the principle of tasks scheduling and reasonably assigning management tasks of the CPU, and developed the bottom driver and application programmes.At last, the paper makes a summary of the course of system development, and points out what the embedded reconfigurable CNC system needs to be improved to guide the follow-up research.