Research And Implementation Of Embeded CNC System Based On OMAPL138 And FPGA

High performance CNC machine tool is a significant and strategic equipment for a nation.CNC system is one of the core technology of the tool machine. It determines the function and performance of CNC machine tools. However, high performance CNC systems are mainly dominated by international companies such as FUNAC, Siemens etc for a long time. Although some domestic CNC industry have made great progress through self research, and a small amount of high-end CNC systems are developed and earn some customers in the domestic market through price competition, some serious drawbacks of our self-owned brand CNC system are obviously remained such as most of our systems are PC-based, high power consumption, poor real-time performance and high hardware cost. Targeting to the above problems, in this paper a new embedded CNC system framework was proposed that is based on heterogeneous dual-core processing OMAPL138 and FPGA and it will further form the foundation of high-performance for five-axis CNC system.Firstly this paper adopt the ARM and DSP and FPGA systems architecture according to the hardware resource demands of high performance CNC system, and chose heterogeneous dual-core processor OMAPL138 and FPGA as the processing core. Then simply introduce two processors. And the overall hardware diagram of the embedded CNC system is given at the end.The second part of this paper mainly designs the OMAPL138 hardware module. OMAPL138 integrates with ARM and DSP kernel, the kernel frequency can up to 456 MHZ.It not only has strong interface and task management capability of ARM, but also has powerful data operation ability of DSP. It is suitable for the main control chip as the CNC system. This paper designs the power management, DDR2, FLASH and other peripheral circuits based on the chip, providing a highly efficient and stable working environment for OMAPL138. This System can realize time/20 us interpolation cycle and supporting eight axis movement control because of powerful operation ability of OMAPL138.The third part is the FPGA module circuit design. The IO ports are not enough for the CNC system. The operand of high speed and high precision CNC is very large, and the control pulse frequency is very high, It will lower the real-time performance if OMAPL138 runs interpolation arithmetic and produces high-frequency pulse at the same time. So in this article, FPGA system extends the IO resources and generates control pulse. And to improve the signal anti-interference and load performance through using light coupling, signal difference and triode expansion flow technology.The fourth part mainly designs the EMIFA bus. First introduced the hardware structure and principle of EMIFA bus, then design the FPGA EMIFA bus module programming.In the end verified the function of the CNC system, It proves the feasibility of this design. This system was applied to leather cutting machine.