Research And Realization Of Motion Control Card Based On DSP And CPLD

Open architecture CNC (computer numerical control) has become the popular trend of CNC technology, and the mode of "industrial computer with motion control card" is the mainstream of the development of open CNC technology. In this mode, the performance of motion control card acts as one key factor to decide system performance.After analyzing and summarizing the current status of related research both at home and abroad, a motion control card was designed, which is based on DSP (Digital Signal Processor) and CPLD (Complex Programmable Logic Device) joint control technology, using PCI bus to communicate with industry PC. It achieved real-time complex trajectory control. The integration technology of introducing PCI bus controller in the CPLD chip improved the reliability and security of frequently plugging PCI device. And we developed a "leakage algorithm" which controls FIFO in the condition of different read and write rates, it not only supplies more efficient and practical API interface , but also makes end users more convenient and efficient to develop applications, and ensured real-time and stability of the hardware output. The sharing of SRAM between DSP and CPLD for data interaction, greatly improved the bandwidth utilization. The introduction of the interpolation algorithm on high-performance DSP realized the complex coordinates computations of the interpolation trajectory. DSP make the motion control card gain the ability of real-time complex trajectory control.Experimental results show that this motion control card based on DSP and CPLD can achieve high-speed, accurate, real-time and stable control of complex trajectory and its interface can support many types of CNC institutions in the market. So, this card is a solution of low cost, high performance and multi-purpose.