The Hardware Design And The Research On Low-level Driver Of Open CNC System

With the rapid development of manufacturing equipment industry, China's growing demand for CNC machine tools. At present, Open CNC system is the main direction of CNC system development due to the characteristics of interoperability, portability and secondary development and so on. On open CNC system, the Europe and the United States and other countries have come in the front, china's research is still in its initial stage. Independent property research of Open CNC system is significant to the manufacturing equipment industry's modernization development of China.The subject of open CNC system design is based on PC + programmable motion control unit, application for AC servo motor. The control mode is feed servo device receive the pulse output mode by double pulse, DAC output analog voltage control spindle inverter and optical encoder feedback the actual location of the feed motor for the system. Operating system adopted real-time operating system RTLinux, programmable motion control card's master chip adopted FPGA, which is widely used in digital communication, the communication between PC and programmable motion control unit using PCI bus.The main work of the paper could be summarized as follows:1. Designed the overall program of the CNC system, for technical requirements, select the FPGA chip, PCI bus interface program and PCI bus interface chip .2. Designed the CNC system's motion control card's hardware, the analysis and design of each module. which including FPGA-related circuit design, servo interface circuit design and PCI bus interfaceircuit design. Finally, analysis the PCB design process and considerations and circuit card testing, Verificating.3. Using VHDL state machine design various modules within the FPGA. This section is on how to realize the communication between PCI drives and motion control card, Motion control interface board control digital servo motor control and process motor position information feedback .4. Realize PCI bus interface chip CH365 driver under the RTLinux.Through reading and writing in the EEPROM chip M24C64, testing and Verificating the PCI driver.5. The preliminary research to do for HAL. Describes interface signals of the spindle driver device and Feed servo device . Finally, this paper design applicated in field CNC Machining.