基于51单片机的usb键盘设计与实现_大学生毕业设计论文.doc

三 江 学 院 本科生毕业设计（论文） 摘 要 关键词：USB；D12；PC Abstract With the rapid development of computer technology and multimedia technology constantly updated, traditional computer peripheral interface because there are many shortcomings have been unable to meet the development needs of the computer.Compared to traditional AT, PS / 2, serial, Universal Serial Bus USB, with fast, flexible and easy to use, easy to expand, support Plug and Play, a series of advantages, such as low cost, has been widely used. This paper describes the 51 series and USB related content, detailing some of the features of the system design, including hardware and software design.During debugging a simple serial communication circuit, through the serial port debugging assistant master USB transfer instructions, which designed the entire program has played a significant role in guiding.Thesis smallest single-chip system consisting of analog keyboard with a USB keyboard hardware system, by learning and exploration D12 chips, with the support of its basic command interface, in conjunction with the corresponding hardware firmware design, making it in the USB protocol, USB module data communication with the PC, the USB keyboard to complete the functional simulation. This paper summarizes research work has elaborated the principle of the USB bus, the system is designed to require the analysis, components and solutions based on the specific requirements of the selected programming for the system to achieve the function of the relevant chips are described in detail in the hardware part of the design as well as the principle of Figure. Keywords:USB；D12；PC 目 录 第一章　绪 论 1 1.1 PC接口简介 1 1.2 USB 接口分析 1 1.3 USB 器件的选择 1 第二章　系统分析 3 2.1 USB总线简介 3 2.2 USB技术指标 3 2.3 USB系统构成 4 第3章　系统硬件设计 6 3.1 STC89C52单片机简介及最小系统 6 3.1.1 单片机发展概况及发展方向 6 3.1.2 单片机特点及结构 6 3.1.3 复位电路设计 8 3.1.4 单片机最小系统硬件设计 9 3.2 PDIUSBD12接口芯片设计 9 3.2.1 USB接口芯片简介 9 3.2.2 USB接口芯片引脚配置 11 3.2.3 USB接口芯片硬件设计 14 3.2.4