The Research And Implementation Of Cnc System Of Milling Machine Based On 80X86 CPU

Embedded technology has been developed rapidly since the 21st century, and it is also wildly used in the numerical control system. It is very important for the development of Chinese numerical control technology to develop an embedded NC product which is function-specific, high reliability and competitive based on embedded technology.An mbedded CNC system for milling machine is designed implemented in this thesis. The 80X86 CPU is used to build the hardware platform for the system. The system adopts the control model of two stage interpolation based on CPU and CPLD. In the model, the CPU executes the calculation of rough interpolation, while the CPLD does the calculation of fine interpolation. The hardware design scheme is discussed in detail in this thesis, which includes power monitoring module, storage module, CPLD module, peripheral interface circuit module and communication module. The code of the driver layer is designed based on the frame of the hardware.The LCD driver, real-time clock driver and USB driver are discussed in detail as they are more complicated. Then the software architecture is analysed, and the file sub-system and the communication sub-system are emphatically introduced. In regard to the core of the CNC system——motion control part, some original design methods are presented. The ability for the interpolation calculation of the system is promoted by the interpolation data pool model. A method of pulses homogenization is proposed based on rough interpolation information through out the whole line segment domain to deal with vibration and losing pulses problems of the stepping motor in practical test. In addition, the implementation of the latest structural scheme of the S-curve type parabolic acceleration and deceleration model is presented.As a result of practical test, the system can be applied in actual processing safely and effectively, which achieves the expected target. The conclusion and prospects for the further research are described in the last part of the thesis.