基于USB总线的可编程函数发生器设计

The Design of USB Based Programmable Function Generator

函数发生器是工程测试、教学科研等领域中不可缺少的一种测试设备。采用符合USB2．0协议规范的CY7C68013A接口芯片，结合Cyclone系列FPGA的硬件描述设计方法，实现频率、相位等波形参数的快速调整。通过虚拟仪器技术使用计算机软件高效地计算和分析波形数据并通过通用串行总线（USB）向硬件模块传递。软硬件之间设计标准的通信接口，应用功能可按用户需求配置，满足了现代系统化测量方法的需求。实验结果表明，所设计的函数发生器能够实现任意形式信号发生的功能，而且方便易用，灵活实用。

Function generator is a kind of indispensable testing equipment in the fields of project testing, teaching and scientific research. The paper introduces the design method in which USB2.0 supported interface chip CYTC68013A and FPGA based on Cyclone are adopted to realize the rapid adjustment of the waveform parameters, such as frequency and phase. In the design scheme, virtual instrument technology is used to enable computer software efficiently calculates and analyses the waveform data and transmits them to the hardware modules through Universal Serial Bus （USB）. The standardized communication interfaces between hardware and software are designed to realize the configuration of application function according the user＇s need, which meets the needs of modern systematic measuring method. The experimental result shows that it can generate arbitrary waveform and is characteristic of convenience and flexibility.