基于USB总线的离散量输入接口板设计与实现

摘要

USB总线技术由于其体积小、热插拔等优势,应用于众多领域,为此,设计与实现了一种基于USB接口的离散量输入接口系统.该系统采用光耦作为输入隔离器件,并使用CPLD实现数据的选通,C51单片机作为主控制器,再通过USB接口芯片CH375实现数据的传输.介绍了硬件和软件设计,给出了CH375的硬件连接、硬件和软件的结构图.该系统可有5V和28 V两种输入,能满足综合航电仿真系统的输入需求.%USB technology, which has the superiorities of small size and hot-plugging, is used in many other fields. So an interface system of discrete input based on USB is designed and realized. The system uses opto-coupler as device of input isolation, and uses CPLD to choose the data, uses C51 microcontroller as the master controller, and then the transmission of data is realized through the USB interface chip CH375. The hardware design and software design are introduced. The hardware connection of CH375, the structure of the hardware and software are given. The system has two kinds of inputs whose voltage are 5 V and 28 V, which can satisfy the input requirements of the integrated avionics simulation system.