The Design And Implement Of CNC System Based On 80486 For Milling Machine

With the rapid development of computer software and hardware, the embedded system technology has gradually grown up. The application of embedded system provides many advantages, including shortening the developing cycle of a product and improving the reliability and cost performance of a system. Embedded system has a serial of other excellent features such as less system cost, tiny volume and low power consumption of single-chip devices as well as perfect developing environment, abundant resources and supporting operating system of PC platforms. It is a mainstream of NC and movement control devices at present and has been widely employed in NC field.Supported by Natural Science Foundation of Jiangsu Province (BK2003005), a design of embedded NC system of milling machine based on microprocessor 80486 is presented in this thesis. The system takes advantage of a two-stage control structure composed of both 80486 system and programming logic device FPGA system. It can hugely simplify system design, improve the density of integration and reliability, and implement 4D-line interpolation and any 2D-arc interpolation. The essential peripheral structure is equipped as well, providing with digital Input/Output and analog output functions. Two-step interpolation method is adopted in system in which 80486 CPU implements rough-interpolation and FPGA system implements DDA fine-interpolation combined with an excellent accelerate/decelerate control algorithm. It ensures the continuity and stability. DOS operating system is employed to guarantee robust stability and real-time property. The software of the system offers a friendly man-machine interface satisfying the requirements of operating habits of users with abundant interactive information.