通用串行总线USB(Universal Serial Bus)是一种新型的微机总线接口规范。随着客户对系统数据采集速度要求的不断提高，USB以其使用方便、易于扩展、速度快等优点而越来越多的应用于数据采集系统中。本文介绍了一种基于USB总线的数据采集系统的设计方法，采用PHILIPS公司的USB接口芯片PDIUSBD12与单片机AT89C51进行通信，并和PC机通信而编制出友善的设备应用程序。该系统用传统的USB总线取代了RS232串行总线，通过对USB协议和设备构架的充分理解，对以单片机89C51和USB接口芯片PDIUSBD12为主的数据采集系统进行了硬件设计和软件编程，并在此设计的基础上给出相应的原理图。硬件设计主要解决的是PDIUSBD12和ADC0809与单片机之
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