Research And Development Of Open NC System Software Architecture Based On LINUX

With the development of the offshore oil extracting engineering, the manufacture engineering of offshore oil pipe and offshore oil platform is also in the rapid development. The bending and welding of all kinds of steel need special numerical control (NC) equipments. The equipments depending on import have many problems and many of them cannot meet the rapid development of the production, we urgently need homemade special NC equipments. Starting from the research and development of special NC system, this paper presented the research and development of the software of open architecture NC system based on Linux, and discussed real time critical technology.Combined with the practical engineering, the technology of the software and hardware needed in realizing the open architecture NC control is studied deeply. The traditional hardware and motion controller are leaved out, meanwhile according to the different requests of the user, process management of the Linux, memory management, interruption management and the real time interface technology of the Linux are adopted to realize the dynamic allocation in the starting and running state, and to realize the transplantable on various soft or hardware platform. This makes the system more adaptable and flexible. In the article, the author takes the methods of system analysis and design besides methods of program design faced with the subject. The stimulation orders replace the machine orders used in inner Linux core such as sti, cli, iret etc. The result is that the real time core supervises the interruption, and prohibits the operation of Linux core about the hardware interruption. To settle the delaying problem due to the interchanging task frequently, the system utilizes the technology of loadable modules to load real time task at the same address. In the facet process schedule, the task scheduler that can be programmable by the user is contrived to schedule task. FIFO buffer technology is used to tackle the exchange of the information between the normal Linux process, Linux core process and the real time process. The open architecture NC System based on Linux developed in this paper has the characteristics of strong function, flexible adaptiveness and fine opening.