USB通信研究及其在虛擬儀器中的應用設計

電子通信論文編號:TX033       論文字數:23415,頁數:51

目    錄
1  緒論   1
2  USB1.1規范和協議概述   2
2.1 USB物理連接   2
2.2 USB系統拓撲結構   3
2.3信號編碼   3
3  USB通信原理   4
3.1通信結構   4
3.2 USB傳輸類型   4
3.3 USB通信流模型   5
3.4 USB傳輸協議   5
3.4.1包的組成   5
3.4.2包的類型   6
4  USB接口設計總體方案   8
4.1 接口芯片選擇   8
4.1.1 AT89C52芯片簡介   9
4.1.2 PDIUSBD12接口芯片簡介   9
4.2 通信接口原理方框圖   14
4.3具體硬件電路設計   14
5  USB微控制器固件編寫   17
5.1固件編寫模型   17
5.2 USB通信處理   18
5.3固件編寫實現   19
5.3.1中斷服務程序流程   19
5.3.2 標準設備請求處理   23
5.3.3 主循環程序流程   26
5.3.4 主要程序說明   26
6  USB驅動程序編寫   30
6.1 WDM驅動程序模型   30
6.2 幾個重要數據結構   31
6.2.1 DRIVER_OBJECT(驅動程序對象)   31
6.2.2 DEVICE_OBJECT（設備對象）   31
6.2.3 IRP（I/O請求包）   32
6.2.4 IO_STACK_LOCATION(I/O堆棧)   32
6.3驅動程序中的主要例程   33
6.3.1 DriverEntry例程   33
6.3.2 AddDevice例程   33
6.3.3 IRP處理例程   34
6.3.4 即插即用管理   34
6.4  USB驅動程序棧   34
6.5配置USB設備   35
6.5.1設備描述符   35
6.5.2配置描述符   37
6.5.3接口描述符   38
6.5.4端點描述符   38
6.5.5 USB串描述符   39
6.5.6完成配置   39
6.5.7取消配置   40
6.6 USB設備訪問   40
7  應用程序設計   41
7.1 獲取設備信息集   41
7.2 識別接口信息   41
7.3 獲得設備路徑名   41
7.4 打開設備   42
7.5 讀寫USB設備   42
7.6 關閉通信   42
8  調試   43
9  結論   44
致謝   45
參考文獻   46

摘   要
隨著計算機技術、通信技術和多媒體技術的發展以及計算機應用的普及，計算機系統的外圍設備越來越多，這些設備并沒有統一的接口標準，設備的安裝和配置都比較復雜。而相對于外設種類和數量的增多，PC機傳統接口從系統與用戶兩個角度都呈現出其固有限制。在此背景下，已成為PC標準的通用串行總線USB為多點數據采集提供了很大的便利，利用USB可以實現較傳統方式更有效、更經濟、點數更多的數據采集。采用USB接口的設備無一例外地支持熱插拔（帶電插拔），用戶在開機狀態時即可將設備連接到電腦主機上，免除了使用戶感到厭煩的重新啟動過程。USB1.1規范中規定了兩種傳輸速率，全速方式的傳輸速率為12Mb/s，低速方式的傳輸速率為1.5Mb/s。因此，USB總線接口與其他類型的接口相比，其優越性就體現在這里，它的傳輸適合各種類型的外設，并支持熱插撥。本文介紹了USB接口的開發方法和流程，從而實現了利用USB接口來實現多點數據采集。在設計中采用的USB芯片為PDIUSBD12，它通常用作微控制器系統中實現與微控制器進行通信的高速通用并行接口，它支持本地的DMA 傳輸。另外在接口的軟硬件設計上介紹了接口電路的連接和固件以及驅動程序的編寫，著重介紹了設備驅動程序的開發方法和過程。本設計中采用的“USB接口芯片+傳統單片+功能電路”的模塊化設計方法，具有很高的靈活性，從而能減小開發的時間、風險以及費用（通過使用已有的結構和減少固件上的投資），從而用最快捷的方法實現最經濟的USB外設的解決方案。通過以上優點，我們可以看出USB接口是作為通信接口的一個理想選擇。
關鍵詞： USB；PDIUSBD12；AT89C52；USB驅動；Windows DDK

Abstract
With the development of computer technology, corresponding technology and multimedia Technology, and the popularization of the use of computer, the computer system peripheral equipment becomes more and more. The equipment does not have unified standard of interface, installation and disposition of the equipment are more complicated. Comparing with the increase of the kinds of peripheral equipment and quantity, the PC traditional demonstrates their inherent destructiveness from system and user these two angles. Under this background, the serial bus USB in common use, which has become PC standard, has offered great convenience to the gathering of multi-point data. Utilizing USB can realize the datum gather, which is more effective, more economic, than the traditional way. The equipment adopting USB interface supports not plug without exception and the user can connect the equipment to the host computer, while the machine is working, having avoided the course of restart. Which is fed up by the user USB1.1 has stipulated two kinds of transferring rate, in a norm: the transferring rate of the full-speed way is 12Mb/s, and that of the low-speed is 1.5Mb/s. So, compared with interface of other types, the bus interface of USB’s inferiority embodies in here. Its transmission is suitable for all kinds of peripheral equipment, supporting hot plug. This text has the development approach and procedure of USB interface, thus realized the gathering of multi-point data by utilizing USB. The USB chip adopted in the design is PDIUSBD12.It’s usually used as the high speed parallel interface in common use to realize the communication with little controller in the little controller system, and it supports the transmission of local DMA, having introduced the development approach and course of the equipment driver procedure emphatically in the design of software and hardware of the interface in addition. The “USB interface chip + traditional single piece + functional circuit' module design method adopted in this design. Has high flexibility, which can reduce the tine of development, the rislc and expenses, thus can come to the solution of the most economic USB peripheral, hardware with the swiftest method. Through the advantages above, We can find out USB interface is an ideal of the communication interface.
Key Words:  USB；PDIUSBD12；AT89C52；USB DRIVER；Windows DDK