说明：  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
(USB (Universal Serial Bus) is a new type of micro- Machine Bus Interface Specification. With customers on the system data acquisition speed continues to improve, with USB convenient, easy to expand, the advantages of faster and more and more used in data acquisition systems. This paper presents a USB-based data acquisition system design methods, PHILIPS companies using the USB interface chip with PDIUSBD12 Progressive AT89C51 OK communication, and communication and PC-friendly and produce equipment applications. The system using traditional USB replace the RS232 serial bus, Through the USB framework agreement and equipment with the full understanding, right to 89 C51 microcontroller and USB interface chip PDIUSBD12-based data acquisition system for the hardware pieces of software design a)