【作者】 刘金凤；

【导师】 杨方；

【作者基本信息】 东北农业大学 ， 农业电气化与自动化， 2004， 硕士

【摘要】 USB接口具有使用方便，数据传输率高，又支持即插即用等特点，但由于USB接口协议复杂，涉及的方面广，特别是软件种类比较多，而且USB芯片种类繁多，使得USB设备的开发非常困难。而且随着USB应用领域的逐渐扩大，人们对于USB的期望也越来越高，希望USB能应用在各种计算机领域中，尤其是在移动数据领域中，希望能通过PDA等移动设备直接和USB外设通信，使得USB能应用在没有PC的领域中。如何将USB应用到嵌入式领域，实现USB的点对点通讯，成为目前USB研究领域的热点。 本文主要介绍了一种USB的主从控制器芯片SL811HS，及其在单片机的嵌入式系统中的应用。在介绍了SL811HS控制器芯片的主要特点的基础上，重点阐述了利用这一芯片在C语言的编程控制之下如何识别U盘的插入和拔出，以及如何将单片机的数据按协议规定写入U盘，其中的协议包括FAT文件协议，USB1.1协议和UFI命令协议。 在器件选择上，除了采用具有主机控制器功能的SL811HS芯片外，其核心芯片采用的是与MCS-51完全兼容的AT89C55，它具有20K的FLASH，不必片外扩展ROM，简化了硬件电路。 本系统实现了单片机对U盘的数据存储，速度快，存储容量大，数据读取方便，直观明了，系统工作安全可靠，抗干扰能力强，可扩展性大，而且针对下位机设计的串口协议简单，可以满足通常数据采集系统的数据存储要求。更多还原

【Abstract】 USB interface device has the characteristic of convenient-use , high-speed and it supports to use once it’s inserted in PC. The development of USB devices is difficult because of the annoying protocol. With the gradually expand of USB’s application, folk’s expectation for USB is higher. People hope that USB can be applied to various fields, especially ambulant data field, and hope movable device can communicate with USB interface device, i.e. USB interface device can be applied to non PC field. How to apply USB to embedded system and realize point-to-point communication. It has became the hot of USB research field now.This thesis introduced the Host-Slave controller SL811HS and the application in the embedded system . In the base of introducing the characteristic of this chip, this thesis mainly explained this chip how to identify the flash disk and how to write data to the flash disk according to several protocols. These protocols include FAT File System Specification , USB Specification and UFI Mass Storage Class.We adopted the AT89C55 which is compatible with MCS-51 products entirely, except the Host controller SL811HS. AT89C55 has 20K bytes of in-system reprogrammable flash memory. So we needn’t to extend the RAM and simplify the hardware.This system has realized the data storage for the flash disk and it has the characteristic of high-speed and mass storage . System’s capacity of anti-jam is strong. For the slave host it has the simple protocol of serial bus which would fit the demands of general purpose of data storage system.Candidate: Liu JinfengMajor: Agricultural electrization and automatization Supervisor: Prof .Yang Fang更多还原