基于USB的DDS控制

采用符合USB2．0协议的FX2系列芯片中的CY7C68013，通过对其可编程接口控制逻辑的合理设计和芯片内部FIFO的有效运用，提出通过USB（通用串行总线）接口控制高性能的DDS（直接数字频率合成器）芯片AD9858的方法。USB接口具有速度快、功耗低、支持即插即用、使用安装方便等优惠。GPIF（通用可编程接口）具有快速、灵活等特点，可以根据需要进行编程，且运行中不需要CPU的干预，仅通过一些CPU标志和中断与增强型8051内核通信。AD9858是一款高性能的DDS器件，可方便快速地产生线性调频、单频脉冲及编码调制信号。因而此方法具有速度快、性能高、占用CPU资源少等特点。

The Controlling on DDS Through USB

A new method of controlling AD9858 which is a kind of DDS chips and of high capabilities through USB is introduced in this paper. This method uses CY7C68013 which is one of the FX2 series conforming USB2.0 protocol. Also, this method designs rationally the general programmable interface （GPIF） and makes efficient use of FIFO inside the chip CY7C68013. The interface of USB has such advantages as high speed, low power consumption, supporting instant pluging in and using, thus it is convenient for using and installing and so on. The general programmable interface （GPIF） has a lot of advantages such as high speed, ference of CPU, and can communicate with internal 8051 through only a few CPU signs and interrupts. AD9858 is one of DDS devices with good performance, and can produce easily a few signals such as linear frequency modulation, single frequency modulation puls, and coding modulation. So, the method has a lot of advantages such as high speed, high capabilities, needing little CPU resource and so on.