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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Analýza USB rozhraní / USB communication protocol analysis

Zošiak, Dušan January 2009 (has links)
Tato práce je zaměřena na zpracování a analýzu USB komunikačního protokolu a implementace jeho jednotlivých částí do FPGA obvodu s využitím programovacího jazyka VHDL. Ve finální podobě by měla práce představovat souhrnný a ucelený dokument popisující principy USB rozhraní a jeho komunikace doplněných praktickým návrhem v jazyce VHDL, který by byl schopen převést data do USB.
32

VGA grabber pro FITkit / FITkit VGA Grabber

Lojda, Jakub January 2015 (has links)
This paper discusses the possibilities of realization of VGA grabber for FITkit. Text is focused on software and hardware implementation possibilities. The first part introduces the reader to the theory of the issue. Next, the paper proposes several options of VGA grabber implementation and brief evaluation of alternatives. The second part describes a chosen architecture of VGA grabber of the featured options and includes a brief summary of the findings of the processor LPC4370 from NXP and USB Video Class UVC, on which the resulting architecture is based. The conclusion includes a brief summary.
33

Analyzátor komunikace na sběrnici USB / USB Bus Communication Analyzer

Jančo, Tomáš January 2016 (has links)
This diploma thesis focuses on designing a USB analyzer. First part of this work describes the USB bus and types of USB data transfers. Next part explores existing USB analyzers. After that, FitKIT Minerva is presented as target platform for USB analyzer implementation. Next part of this project is dedicated to design the analyzer architecture and its parts: physical layer circuit, communication interface and user interface. Rest of the work show how the analyzer was implemented and evaluates the results achieved. Final result of this thesis is a working USB analyzer on FitKIT Minerva platform with graphical user interface accesible via web browser.
34

USB dongles for mobile broadband : Data communications for laptop computers

Liu, Enfei January 2015 (has links)
Today a growing number of people need to work on laptops with wireless Internet connection. There are two common wireless Internet access solutions: wireless local area network (WLAN) via hotspot, and high speed wide area cellular network via mobile broadband device such as 3G/4G Universal Serial Bus (USB) dongle. USB dongle was the pioneer product in 3G/4G market, and it is still a popular device in many countries. Mobile broadband can offer both high speed access and mobility. Technically mobile broadband allows Internet connection as long as your mobile transceiver can access your cellular network operator’s network. However, in practice the data rates experienced by a user via mobile broadband are not comparable to the data rates that are available via WLAN. Moreover, mobile broadband has been implemented according to multiple different standards. Hence, in order to provide a user with locally optimal service requires that user must make use of heterogeneous networks. Furthermore, the variety of networks gets increasing due to the emergence of various 4G networks. The aim of this thesis is to explore how heterogeneous networks could be exploited to provide a user of a laptop computer with locally optimal service, while hiding the complexity of this heterogeneous service. The research focuses on the implications of integrating multiple network interfaces into a single USB dongle. Our research shows that multi-mode USB dongle is still needed in market, though there are competitions from smartphones and mobile WiFi devices. We point out that the PPP (Point to Point Protocol) based USB dongle should update to Ethernet USB protocols such as RNDIS (Remote Network Driver Interface Specification) or USB CDC (Communications Device Class) protocols. Furthermore, we suggest a USB dongle should be able to work as a WLAN access point to share Internet with other mobile devices, and it should also work as a WLAN client which can join other hotspots. If hotspot operators can authenticate USB dongles by SIM cards, then users can easily access a great number of hotspots belong to these operators. / Mer än någonsin behöver människan arbeta med bärbara datorer med anslutning till trådlöst Internet. Det finns två vanliga trådlösa Internet-anslutningar: trådlöst lokalt nätverk (WLAN på engelska) via en hotspot, eller höghastighets mobilnät via mobilt bredband som 3G/4G Universal Serial Bus (USB) dongel. USB dongeln var pionjär produkten inom 3G/4G marknaden, och den är fortfarande en populär enhet i många länder. Mobilt bredband kan erbjuda både tillgång till höga hastighet och bra mobilitet. Mobilt bredband tillåter, rent tekniskt, användaren hålla en Internet-anslutning så länge mobilen har tillgång till mobilnätets operatörsnät. Men i praktiken är datahastigheterna, som användaren upplever ha via det mobila bredbandet, inte jämförbar med de datahastigheter som är tillgängliga via WLAN. Dessutom har mobilt bredband implementerats enligt flera olika standarder. Således, för att förutse en användare med en optimal lokal tjänst, krävs det att användaren måste använda heterogena nätverk. Dessutom blir olika nätverk allt större på grund av uppkomsten av olika 4G-nät. Syftet med denna avhandling är att undersöka hur heterogena nätverk skulle kunna utnyttjas för att förutse en laptop användare med optimal lokal nätverksservice, samtidigt dölja komplexiteten för användaren om den heterogena tjänsten. Forskningen fokuserar på konsekvenserna av att integrera flera nätverksgränssnitt till en enda USB-dongel. Vår forskning visar att det fortfarande behövs en multi-mode USB dongel på marknaden, dock existerar det konkurrens från smartphones och mobila WiFi-enheter. Vi påpekar även i avhandlingen att PPP (Point-to-Point Protocol) baserade USB dongeln bör uppdateras till Ethernet USB-protokoll, såsom RNDIS (Remote Network Driver Interface Specification) eller USB CDC (Communications Device Class) protokoll. Vidare föreslår vi att en USB-dongel bör kunna fungera som en kopplingspunkt för att dela Internet med andra mobila enheter, och att den också bör fungera som en WLAN-klient som kan ansluta sig till andra hotspots. Om hotspot operatörer kan autentisera USB-donglar genom SIM-kort, så kan användarna enkelt få tillgång till ett stort antal hotspots som tillhör dessa operatörer.
35

Modernisering av testutrustning / Modernization of Testing Equipment

Gustafsson, Thomas January 2012 (has links)
Rapporten beskriver arbetet med att modernisera en testutrustning för ett robotsystem. Den nya testutrustningen skulle moderniseras till att använda USB-gränssnitt istället för RS232-gränssnitt för kommunikation mellan dator och den övriga hårdvaran. Arbetet börjar med kravspecifikation och slutar med en fungerande produkt. I det innefattas en kortare förklaring av USB-gränssnittet och dess skillnader från RS232-gränssnittet, en utredning för att finna den bästa lösningen för att förverkliga USB-kommunikationen med utrustningen och konstruktion av elektronik för att styra signaler och spänningsmatningar till robotsystemet. / This report describes the work to modernize a test equipmentt for a missile system. The new test equipment would be upgraded to use a USB interfaces instead of RS232 interface for communication between the computer and the rest of the hardware. The work begins with the specification and ends with a working product. In that included a brief explanation of the USB interface and its differences from the RS232 interface, an investigation to find the best solution for implementing USB communication with the equipment and construction of electronics to control signals and power supplies to the missile system.
36

Řízení komunikace po sběrnici USB / Control of the communication on the USB

Hlavica, Zdeněk January 2008 (has links)
The aim of Master’s thesis Control of the communication on the USB is realization hardware and software designed for microcontroller C8051F120 what is enabling recording of data on memory medium Flash drive. It includes study of USB, transfer protocols, which are needed and file system. The thesis deals about host type USB controllers and about USB controller MAX3421E fy Maxim, which has been choosen for development of software. It is required ability to create directories and files including recording data to file and ability of reading data from files in the file system FAT16.
37

Regulovatelný zdroj napájený a řízený pomocí USB / Adjustable source supplied and controlled via USB

Pavlíček, Petr January 2010 (has links)
Master’s thesis deals with design and realization of power supply, which is supplied and controlled via USB bus. In theoretical part there are described principles of USB communication drivers which ensures this communication, there are described principles of linear voltage regulators and basic types of DC/DC converters. Mentioned is also PID regulator theory. Practical part aims for design of suitable DC/DC converter topology and creating algorithms for driving this converter. Next there is created PC program which drives power supply and there are also accomplished basic power supply measurements. The result of this thesis is functional power supply supplemented with PCB.
38

A FREQUENCY SCAN/FOLLOWING SCAN TWOWAY CARRIER ACQUISITION METHOD FOR USB SYSTEM

Jiaxing, Liu, Hongjun, Yang 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper introduces a frequency scan/following scan twoway carrier acquisition method for USB and its following scan slope decision algorithm. Some measures are used to improve twoway acquisition speed such as selecting initiation direction and returning to zero in the shortest path, which can be implemented by software. Theoretic analysis, mathematical expression, design method and experiment results are provided. Practical engineering application shows the twoway acquisition using this new method has many advantages such as fast speed, low cost and programmability. The method has been used in Chinese USB system widely.
39

Desarrollo de una interfaz USB para el control de estaciones de radio HF y VHF para comunicación de datos / Him Cuper Cansaya Herrera

Cansaya Herrera, Him Cuper 09 May 2011 (has links)
La presente tesis describe el trabajo de ingeniería, investigación, medición, cálculo, diseño, implementación e instalación de un equipo electrónico denominado Placa Estación USB, el cual se encontrará en estaciones de radios HF y/o VHF rurales y en estos lugares remotos se encargará de automatizarlas, logrando de esta manera conocer el estado de los parámetros más importantes de cada locación y así dejarlos listos para poder leerlos desde cualquier punto de la red. También se trata de optimizar el uso de cada estación facilitando las funciones del usuario no especializado. / Tesis
40

Diseño de un sistema de adquisición de datos utilizando el protocolo usb en un microcontrolador AVR

Nole Calle, Richard Armando 11 June 2014 (has links)
Existen diversas tecnologías de comunicación con una computadora para la adquisición de datos, entre los más comunes se encuentran: PCI, USB, Ethernet, Firewire, puerto serial, etc. Dentro de ellos, el USB destaca por su configuración automática, bajo costo y facilidad de uso. A pesar de existir varios sistemas de adquisición de datos en el mercado, su uso se ve restringido debido a sus altos costos y por poder usarlo sólo con las aplicaciones y drivers del proveedor. En el presente trabajo se diseña un sistema de adquisición de datos con interface USB utilizando un microcontrolador Atmel de la familia AVR XMEGA, buscando en todo momento obtener la máxima tasa de transferencia posible. Para ello se desarrolla una aplicación en el microcontrolador que permita leer datos adquiridos de cuatro canales del ADC del microcontrolador. Asimismo, se desarrolla una clase USB propietaria que define cómo se van a trasferir los datos, qué tipo de transferencias USB se van a usar y cuál va a ser su máxima tasa de transferencia posible. En el lado de la computadora, se desarrolla una aplicación en lenguaje C que permita a la computadora poder comunicarse con el microcontrolador a través del bus USB. Para el desarrollo del firmware del microcontrolador se tomó como base el framework USB que provee Atmel (ASF 3.1.3, Atmel Software Framework), y posteriormente fue implementado en la tarjeta de evaluación XMEGA – A3BU XPLAINED con una frecuencia de CPU de 32MHz. Se obtuvo que en promedio se puede transmitir datos a 8.46Mbps usando un alto nivel de optimización del compilador. Se concluye que si se quiere obtener mejores tasas de transferencia se debe mejorar una serie de factores como: MIPS del microcontrolador y optimización del framework USB de Atmel. Finalmente, se recomienda portar este trabajo a microcontroladores que soporten el modo “Alta Velocidad” (del inglés High Speed) del USB 2.0, cuya velocidad por bit es de 480Mbps, así como desarrollar las etapas de preprocesamiento de las señales: amplificación, filtrado, e aislamiento de las señales que se quieran enviar por la interfaz USB. / Tesis

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