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USb-I

  • USB/EPP轉(zhuǎn)接系統(tǒng)的硬件設(shè)計(jì)與分析

    摘要:設(shè)計(jì)并實(shí)現(xiàn)了一個(gè)USB/EPP 轉(zhuǎn)接系統(tǒng),給出其硬件設(shè)計(jì)方案并討論了相關(guān)技術(shù)細(xì)節(jié), 使其實(shí)現(xiàn)USB 接口到EPP接口的相互數(shù)據(jù)轉(zhuǎn)發(fā)。使僅具有EPP 接口的傳統(tǒng)儀器設(shè)備借助于USB/EPP 轉(zhuǎn)接系統(tǒng)擁有USB 總線所提供的即插即用和設(shè)備插架特性, 方便其通過(guò)USB 接口靈活接入同時(shí)擁有多個(gè)外設(shè)的計(jì)算機(jī)主機(jī)系統(tǒng)。關(guān)鍵詞:USB;EPP;轉(zhuǎn)接系統(tǒng)中圖分類號(hào):TP368.3 文獻(xiàn)標(biāo)識(shí)碼:A文章編號(hào):1008- 0570(2005)11- 2- 0166- 03 在傳統(tǒng)的I/O 模式中,計(jì)算機(jī)外設(shè)通常映射為CPU 中固定I/O 地址,要求由主機(jī)分配一個(gè)指定的IRQ 中斷請(qǐng)求。由于PC 機(jī)的端口和中斷資源有限,因而使外設(shè)的可擴(kuò)展性受到局限;同時(shí),隨著電腦應(yīng)用的拓展,PC 機(jī)的外設(shè)接口越來(lái)越多,外設(shè)對(duì)系統(tǒng)資源的獨(dú)占性也容易導(dǎo)致系統(tǒng)資源沖突。由于各種外部設(shè)備不斷增加,容易導(dǎo)致各種I/O 沖突。由Intel、Compaq、Microsoft、IBM等廠商所提出的USB 總線標(biāo)準(zhǔn),基于即插即用和設(shè)備插架技術(shù),設(shè)備接入時(shí)不影響應(yīng)用程序的運(yùn)行,具有良好的可擴(kuò)充性和擴(kuò)展的方便性。目前USB 協(xié)議已經(jīng)發(fā)展到了最新的2.0 版本,可支持峰值傳輸速率為480Mbps 的高速外設(shè),可提供4~8 個(gè)USB 2.0 接口,同時(shí)通過(guò)USB 集線器(HUB)的擴(kuò)展還可以支持多達(dá)127 個(gè)外設(shè)同時(shí)連接,基本上解決了各種外設(shè)同時(shí)存在同時(shí)使用的所有問(wèn)題。基于USB 接口的上述優(yōu)點(diǎn),目前的計(jì)算機(jī),特別是筆記本計(jì)算機(jī)基本上都只配備USB 接口,而取消了傳統(tǒng)的串口和并口,這對(duì)那些以前購(gòu)置的需要與計(jì)算機(jī)進(jìn)行通信而只有串口或并口的各種儀器的繼續(xù)使用造成了極大的障礙。 針對(duì)傳統(tǒng)的數(shù)字化儀器與計(jì)算機(jī)通信中存在的接口不足的問(wèn)題,本文設(shè)計(jì)了一個(gè)USB/EPP 轉(zhuǎn)接系統(tǒng),使其能夠從計(jì)算機(jī)的USB 接口接收數(shù)據(jù),經(jīng)過(guò)格式轉(zhuǎn)換,從USB/EPP 轉(zhuǎn)接系統(tǒng)的并行接口EPP 發(fā)送給傳統(tǒng)的儀器設(shè)備;同時(shí)也能夠從USB/EPP 轉(zhuǎn)接系統(tǒng)的并行接口EPP 接收數(shù)據(jù),將其轉(zhuǎn)化為USB 幀格式,并發(fā)送到計(jì)算機(jī)的USB 接口。從而使僅具有EPP 接口的傳統(tǒng)儀器設(shè)備借助于USB/EPP 轉(zhuǎn)接系統(tǒng),可以繼續(xù)正常使用。2 USB 總線2.1 USB 系統(tǒng)描述及總線協(xié)議USB 是一種電纜總線,支持在主機(jī)和各種即插即用外設(shè)之間進(jìn)行數(shù)據(jù)傳輸。由主機(jī)預(yù)定的標(biāo)準(zhǔn)協(xié)議使各種設(shè)備分享USB 帶寬,當(dāng)其它設(shè)備和主機(jī)在運(yùn)行時(shí),總線允許添加、設(shè)置、使用以及拆除外設(shè),這為多個(gè)儀器設(shè)備共享同一個(gè)主計(jì)算機(jī)提供了可能。USB 協(xié)議采用了管道模型的軟硬件協(xié)議,摒棄了一般外設(shè)協(xié)議的端口映射方式,從而有效地避免了計(jì)算機(jī)應(yīng)用系統(tǒng)I/O 端口地址沖突。根據(jù)功能劃分,一個(gè)USB 系統(tǒng)由三個(gè)部分組成:即USB 互連、USB 主機(jī)和USB 設(shè)備。圖1 給出了USB系統(tǒng)的通用拓?fù)浣Y(jié)構(gòu)。

    標(biāo)簽: USB EPP 轉(zhuǎn)接

    上傳時(shí)間: 2013-10-09

    上傳用戶:半熟1994

  • Stantor is a Domotic project. It is a SCADA for the computer interface board K8055 (USB bus), K8000

    Stantor is a Domotic project. It is a SCADA for the computer interface board K8055 (USB bus), K8000 (I2C bus) , X10 modules and also Webcam. It uses Browser WEB, I-mode and Wap2/Wap1, Apache,mySQL, PHP, javascript. It run with Linux 2.4 or 2.6 and XP

    標(biāo)簽: interface computer Stantor Domotic

    上傳時(shí)間: 2013-12-18

    上傳用戶:sevenbestfei

  • This application note describes a method for developing block-oriented I/O device drivers for appli

    This application note describes a method for developing block-oriented I/O device drivers for applications that use the DSP/BIOS real-time kernel and includes examples that run with Code Composer Studio v2.1 on the Texas Instruments TMS320C5402 and TMS320C6711 DSP Starter Kits (DSKs). The device driver model presented here has now been superceded with an updated version that supports not only block oriented devices, but also devices such as UARTs, PCI and USB buses and Multimedia cards. Documentation on the updated driver model as well as example drivers and source code can be found in the Device Driver Developer s Kit product now available for download from the TI Developer s Village.

    標(biāo)簽: block-oriented application developing describes

    上傳時(shí)間: 2015-07-07

    上傳用戶:kelimu

  • //打開(kāi) USB 口讀寫(xiě), 由驅(qū)動(dòng)程序的 Pipe 名確定 HANDLE hPipe = OpenMyDevPipe("MyPipe1") //驅(qū)動(dòng)程序里面的 Pipe 名, 對(duì)應(yīng)訪問(wèn)某個(gè)端點(diǎn)

    //打開(kāi) USB 口讀寫(xiě), 由驅(qū)動(dòng)程序的 Pipe 名確定 HANDLE hPipe = OpenMyDevPipe("MyPipe1") //驅(qū)動(dòng)程序里面的 Pipe 名, 對(duì)應(yīng)訪問(wèn)某個(gè)端點(diǎn)的 I/O, 這里我亂寫(xiě)的, 需要與驅(qū)動(dòng)一致 if(hPipe != INVALID_HANDLE_VALUE) //打開(kāi) Pipe 成功 { ReadFile(hPipe, Buffer, BufSize, &nBytesRead, NULL) //從 hPipe 里讀取數(shù)據(jù)到 Buffer 里 //WriteFile(hPipe, Buffer, BytesToWrite, &nBytesWritten, NULL) //把 Buffer 里面的 BytesToWrite 字節(jié)寫(xiě)入 hPipe CloseHandle(hPipe) } //使用 DeviceIoControl 訪問(wèn) USB 設(shè)備 HANDLE hDevice = OpenMyDevice() if(hDevice != INVALID_HANDLE_VALUE) //打開(kāi)設(shè)備成功 { //這些 DeviceIoControl 功能都是由設(shè)備定義的, 具體看設(shè)備和驅(qū)動(dòng)的資料 if(DeviceIoControl(hDevice, IOCTL_READ_xxxx, &IOBlock, sizeof(IOBLOCK), &c, 1, &nBytes, NULL)) { //成功 } CloseHandle(hDevice) }

    標(biāo)簽: Pipe OpenMyDevPipe MyPipe1 HANDLE

    上傳時(shí)間: 2014-11-25

    上傳用戶:stampede

  • 版本歷史 -------------------------------------------------------------- [x] 修正 [+] 新增[*] 改進(jìn)/改變 [i] 信息(

    版本歷史 -------------------------------------------------------------- [x] 修正 [+] 新增[*] 改進(jìn)/改變 [i] 信息(請(qǐng)仔細(xì)閱讀) 當(dāng)前版本:v0.6 -------------------------------------------------------------- [i] 新增70種設(shè)備代碼 [i] 目前對(duì)外置HUB支持不好,測(cè)試時(shí)請(qǐng)不要使用USB HUB,這一問(wèn)題會(huì)在未來(lái)版本中改進(jìn)。 [x] 修正了接入設(shè)備后按“刷新”程序報(bào)錯(cuò) [x] 優(yōu)化了內(nèi)存使用 關(guān)于SigmaTel 35系列的分辨: 由于SigmaTel 3500系列產(chǎn)品型號(hào)非常亂,并且很多廠商也會(huì)自行修改設(shè)備識(shí)別碼,造成識(shí)別錯(cuò)誤。但如果本軟件識(shí)別出芯片是SigmaTel 3500系列的話,則可從設(shè)備的速度及具體配置來(lái)判斷,目前使用的最多的型號(hào)便是STMP3502與STMP3520,如果USB速度是480Mbps則可認(rèn)定芯片為STMP3520,否則為STMP3502。更加細(xì)節(jié)的識(shí)別方式,我們將會(huì)刊登在我們的論壇上:forum.easydigi.com

    標(biāo)簽: 版本 改變

    上傳時(shí)間: 2013-12-26

    上傳用戶:彭玖華

  • i.mx27開(kāi)發(fā)板的整套詳細(xì)原理圖

    i.mx27開(kāi)發(fā)板的整套詳細(xì)原理圖,包括:DDR SDRAM, NAND FLASH, NOR FLASH, USB OTG, USB HOST,FEC PHY, UART,JTAG等等接口

    標(biāo)簽: mx 27 開(kāi)發(fā)板 原理圖

    上傳時(shí)間: 2013-12-15

    上傳用戶:yuanyuan123

  • Very simple USB 1.1 PHY. Includes all the goodies: serial/parallel conversion, bit stuffing/unstuff

    Very simple USB 1.1 PHY. Includes all the goodies: serial/parallel conversion, bit stuffing/unstuffing, NRZI encoding decoding. Uses a simplified UTMI interface. Currently doesn t do any error checking in the RX section [should probably check for bit unstuffing errors]. Otherwise complete and fully functional. There is currently no test bench available. This core is very simple and is proven in hardware. I see no point of writing a test bench at this time.

    標(biāo)簽: conversion Includes parallel stuffing

    上傳時(shí)間: 2017-03-11

    上傳用戶:hn891122

  • :以ARM9系列芯片S I、R912I W4,1X為核心

    :以ARM9系列芯片S I、R912I W4,1X為核心,主要針對(duì)中低檔扣普及性車型,設(shè)計(jì)和開(kāi)發(fā)符合國(guó)家標(biāo)準(zhǔn)的新型汽車行駛記錄儀. 介紹了行駛記錄儀硬件,軟件結(jié)構(gòu).包括數(shù)據(jù)采集、數(shù)據(jù)存儲(chǔ)、與P(、機(jī)進(jìn)行串口和USB通訊、I CD顯示、GI S定位系統(tǒng)等在內(nèi)的硬軟件的組成部分.通過(guò)模擬實(shí)驗(yàn)研究。該記錄儀可靠性高、使用方便; 自動(dòng)導(dǎo)航和定位系統(tǒng),包括全球衛(wèi)星定位系統(tǒng)和電子地圖也取得了較好的使用效果.

    標(biāo)簽: R912I ARM9 系列芯片 核心

    上傳時(shí)間: 2014-01-26

    上傳用戶:huql11633

  • USB is quick hot-pluggable, ease of use, connect and power, this book isn t too technical but practi

    USB is quick hot-pluggable, ease of use, connect and power, this book isn t too technical but practical, helps to develop I/O devices with examples and prototypes, intended for those who have programming and electronics skills.

    標(biāo)簽: hot-pluggable technical connect practi

    上傳時(shí)間: 2013-12-26

    上傳用戶:it男一枚

  • userial is an Free project building an USB to I2C/SPI/GPIO bridge, using the Atmel AT90USB647 chip.

    userial is an Free project building an USB to I2C/SPI/GPIO bridge, using the Atmel AT90USB647 chip. Hardware and Software are released under an Open Source licence. It supports the following interfaces: * USB interface (serial emulation) * JTAG * I2C (TWI) * SPI * 8 General purpose digital I/O * 4 Analog to Digital converters (currently no firmware support)

    標(biāo)簽: USB building userial project

    上傳時(shí)間: 2013-12-25

    上傳用戶:小鵬

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