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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.
91

Design, Implementation and Evaluation of a Configurable NoC for AcENoCs FPGA Accelerated Emulation Platform

Lotlikar, Swapnil Subhash 2010 August 1900 (has links)
The heterogenous nature and the demand for extensive parallel processing in modern applications have resulted in widespread use of Multicore System-on-Chip (SoC) architectures. The emerging Network-on-Chip (NoC) architecture provides an energy-efficient and scalable communication solution for Multicore SoCs, serving as a powerful replacement for traditional bus-based solutions. The key to successful realization of such architectures is a flexible, fast and robust emulation platform for fast design space exploration. In this research, we present the design and evaluation of a highly configurable NoC used in AcENoCs (Accelerated Emulation platform for NoCs), a flexible and cycle accurate field programmable gate array (FPGA) emulation platform for validating NoC architectures. Along with the implementation details, we also discuss the various design optimizations and tradeoffs, and assess the performance improvements of AcENoCs over existing simulators and emulators. We design a hardware library consisting of routers and links using verilog hardware description language (HDL). The router is parameterized and has a configurable number of physical ports, virtual channels (VCs) and pipeline depth. A packet switched NoC is constructed by connecting the routers in either 2D-Mesh or 2D-Torus topology. The NoC is integrated in the AcENoCs platform and prototyped on Xilinx Virtex-5 FPGA. The NoC was evaluated under various synthetic and realistic workloads generated by AcENoCs' traffic generators implemented on the Xilinx MicroBlaze embedded processor. In order to validate the NoC design, performance metrics like average latency and throughput were measured and compared against the results obtained using standard network simulators. FPGA implementation of the NoC using Xilinx tools indicated a 76% LUT utilization for a 5x5 2D-Mesh network. A VC allocator was found to be the single largest consumer of hardware resources within a router. The router design synthesized at a frequency of 135MHz, 124MHz and 109MHz for 3-port, 4-port and 5-port configurations, respectively. The operational frequency of the router in the AcENoCs environment was limited only by the software execution latency even though the hardware itself could be clocked at a much higher rate. An AcENoCs emulator showed speedup improvements of 10000-12000X over HDL simulators and 5-15X over software simulators, without sacrificing cycle accuracy.
92

Estudo e implementação de operações em ponto fixo em FPGA com VHDL 2008: aplicação em controle de sistemas em tempo discreto

Oliveira, Alisson Antônio de 13 December 2012 (has links)
Existem máquinas que necessitam de uma grande velocidade de processamento para seu correto trabalho, essas máquinas possuem um tempo de processamento de resposta crítico. Quando considera-se este aspecto somado à necessidade de um controle do comportamento estático e dinâmico de um sistema chega-se ao controlador com fortes demandas de tempo de execução. Essa dissertação compara controladores discretos implementados em ponto fixo, com diferentes precisões, usando para tanto a simulação do comportamento de controladores confeccionados em linguagem de comandos Matlab e em linguagem VHDL 2008. Esta última está em desenvolvimento e padronização pelo IEEE. A linguagem VHDL é usada nas FPGAs que são dispositivos de alta velocidade e capacidade de processamento paralelo. O principal objetivo do trabalho é o estudo e a implementação de controladores discretos em FPGA com o auxílio da linguagem VHDL 2008, determinando suas virtudes e limitações, em particular quanto à estrutura de programação, análise de erro e a demanda por recursos. Os resultados alcançados demonstram que algumas melhorias ainda precisam ser feitas para que o VHDL 4.0, conhecido como VHDL 2008, seja entregue ao mercado como padrão estável. Entretanto, quando conhecidas suas limitações, já é possível seu uso em implementações com conversão de sinais discretos para analógicos, como é o caso de controle e simulação de sistemas dinâmicos como servomecanismos. / There are machines that need large processing speed for its correct working, these machines have a critical time response processing. When it is considered that aspect coupled with the need for control of static and dynamic behavior of a system arrives at the controller with strong demands on runtime. This dissertation compares discrete controllers implemented in fixed point with different accuracies, using for both the simulation of the behavior of controllers manufactured in Matlab command language and VHDL 2008. VHDL 2008 still in development and standardization by the IEEE. The VHDL language is used in FPGAs that are high speed devices with parallel processing capability. The main objective of this work is the study and implementation of discrete controllers in FPGA with the help of the VHDL 2008 language, determining its strengths and limitations, particularly in regard to the structure of programming, error analysis and demand for resources. Results show that accuracy still need some improvements a standard to the VHDL 4.0, known as VHDL 2008, is delivered to the market a stable standard. However, knowing it limitations, it is possible implementations and use in conversion of analog signals to discrete, such as control and dynamic systems simulation like servomechanisms.
93

Implementação em FPGA de compensadores de desvios para conversor analógico digital intercalado / FPGA implementation of time interleaved analog to digital converter mismatches compensators

Hofmann, Maicon Bruno 15 March 2016 (has links)
Este trabalho apresenta a modelagem e implementação em FPGA de sistemas digitais de compensação de desvios para TIADC. O desenvolvimento de todo este trabalho seguiu uma metodologia top-down. Seguindo esta metodologia foi elaborada a modelagem comportamental de um TIADC de dois canais e seus respectivos desvios de offset, ganho e clock skew em Simulink. Além da modelagem comportamental de sistemas digitais para a compensação destes desvios. Para o desvio de clock skew foi utilizada a compensação através de filtros de delay fracionário, mais especificamente, a eficiente estrutura de Farrow. A definição de qual método seria utilizado para o projeto do filtro, e da estrutura de Farrow, exigiu um estudo de diversos métodos de projeto apresentados na literatura. Os sistemas digitais de compensação modelados foram convertidos em código VHDL, para implementação e validação em FPGA. A validação destes sistemas foi realizada utilizando a metodologia de teste FPGA In Loop. Os resultados obtidos com os compensadores de desvio do TIADC demonstram o elevado ganho de desempenho fornecido por estas estruturas. Além deste resultado, este trabalho ilustra o potencial das metodologias de desenvolvimento, implementação e teste em FPGA utilizadas para a obtenção destes compensadores. / This work presents the modeling and FPGA implementation of digital TIADC mismatches compensation systems. The development of the whole work follows a top-down methodology. Following this methodology was developed a two channel TIADC behavior modeling and their respective offset, gain and clock skew mismatches on Simulink. In addition was developed digital mismatch compensation system behavior modeling. For clock skew mismatch compensation fractional delay filters were used, more specifically, the efficient Farrow struct. The definition of wich filter design methodology would be used, and wich Farrow structure, required the study of various design methods presented in literature. The digital compensation systems models were converted to VHDL, for FPGA implementation and validation. These system validation was carried out using the test methodology FPGA In Loop . The results obtained with TIADC mismatch compensators show the high performance gain provided by these structures. Beyond this result, these work illustrates the potential of design, implementation and FPGA test methodologies.
94

Implementação em FPGA de compensadores de desvios para conversor analógico digital intercalado / FPGA implementation of time interleaved analog to digital converter mismatches compensators

Hofmann, Maicon Bruno 15 March 2016 (has links)
Este trabalho apresenta a modelagem e implementação em FPGA de sistemas digitais de compensação de desvios para TIADC. O desenvolvimento de todo este trabalho seguiu uma metodologia top-down. Seguindo esta metodologia foi elaborada a modelagem comportamental de um TIADC de dois canais e seus respectivos desvios de offset, ganho e clock skew em Simulink. Além da modelagem comportamental de sistemas digitais para a compensação destes desvios. Para o desvio de clock skew foi utilizada a compensação através de filtros de delay fracionário, mais especificamente, a eficiente estrutura de Farrow. A definição de qual método seria utilizado para o projeto do filtro, e da estrutura de Farrow, exigiu um estudo de diversos métodos de projeto apresentados na literatura. Os sistemas digitais de compensação modelados foram convertidos em código VHDL, para implementação e validação em FPGA. A validação destes sistemas foi realizada utilizando a metodologia de teste FPGA In Loop. Os resultados obtidos com os compensadores de desvio do TIADC demonstram o elevado ganho de desempenho fornecido por estas estruturas. Além deste resultado, este trabalho ilustra o potencial das metodologias de desenvolvimento, implementação e teste em FPGA utilizadas para a obtenção destes compensadores. / This work presents the modeling and FPGA implementation of digital TIADC mismatches compensation systems. The development of the whole work follows a top-down methodology. Following this methodology was developed a two channel TIADC behavior modeling and their respective offset, gain and clock skew mismatches on Simulink. In addition was developed digital mismatch compensation system behavior modeling. For clock skew mismatch compensation fractional delay filters were used, more specifically, the efficient Farrow struct. The definition of wich filter design methodology would be used, and wich Farrow structure, required the study of various design methods presented in literature. The digital compensation systems models were converted to VHDL, for FPGA implementation and validation. These system validation was carried out using the test methodology FPGA In Loop . The results obtained with TIADC mismatch compensators show the high performance gain provided by these structures. Beyond this result, these work illustrates the potential of design, implementation and FPGA test methodologies.
95

Sistema para controle de maquinas robotizadas utilizando dispositivos logicos programaveis / System to control of robotic machines using programmable logic devices

Guardia Filho, Luiz Eduardo 07 June 2005 (has links)
Orientador: Marconi Kolm Madrid / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-04T17:12:57Z (GMT). No. of bitstreams: 1 GuardiaFilho_LuizEduardo_M.pdf: 2405031 bytes, checksum: b724836217b8586950a9ffabcd235f35 (MD5) Previous issue date: 2005 / Resumo: Este trabalho de mestrado teve o propósito de projetar e construir um sistema de hard-ware capaz de realizar o controle de máquinas robotizadas em tempo real. Foi dada uma abordagem usando técnicas de processamento paralelo e eletrônica reconfigurável com o uso de dispositivos lógicos programáveis. Mostrou-se em função dos resultados das implementações que o sistema proposto é eficiente para ser utilizado no controle de robôs baseado em modelos matemáticos complexos como cinemático direto/inverso, dinâmico e de visão artificial. Esse mesmo sistema prevê sua utilização para os quatro níveis hierárquicos envolvidos em plantas que se utilizam de controle automático: supervisão, tarefas, trajetória e servomecanismos. O sistema possui interfaces de comunicação USE e RS-232, conversores A/D e D/A, sistema de processamento de imagens (entradas e saídas de sinais de vídeo analógico), portas E/S, chaves e leds para propósito geral. A eficiência foi comprovada através de experimentações práticas utilizando sistemas robóticos reais como: sistema de um pêndulo acionado, robô redundante de 4GDL denominado Cobra, e solução em hardware de funções importantes no sentido da resolução dos modelos matemáticos em tempo real como funções transcendentais / Abstract: This work had as purpose the project and build of a hardware system with abilities to accomplish the real time control of robotic machines. It was given an approach using tech-niques of parallel processing and programmable electronics configuration with programmable logic devices. According to the implementation results, it was shown that this proposed sys-tem is efficient to be used for controlling robots based on complex mathematical models, like direct/inverse kinematics, dynamics and artificial vision. This system foresees its use for the four hierarchical levels involved in industrial plants that use automatic control: supervision, tasks, trajectory /path and servomechanisms. The system has USE and RS-232 communica-tion interfaces, A/D and D/A converters, image processing capabilities (with input/output for analog video signals), I/O ports, and switches and leds for general purpose. Its efficiency is demonstrated through practical experimentations using real robotic systems as: a driven pendu-lum system, a redundant 4 DOF robot called "Cobra", and a hardware solution for important functions in the sense of real time mathematical models computing, like the transcendental functions / Mestrado / Automação / Mestre em Engenharia Elétrica
96

Evaluation of high-level synthesis tools for generation of Verilog code from MATLAB based environments

Bäck, Carl January 2020 (has links)
FPGAs are of interest in the signal processing domain as they provide the opportunity to run algorithms at very high speed. One possible use case is to sort incoming data in a measurement system, using e.g. a histogram method. Developing code for FPGA applications usually requires knowledge about special languages, which are not common knowledge in the signal processing domain. High-level synthesis is an approach where high-level languages, as MATLAB or C++, can be used together with a code generation tool, to directly generate an FPGA ready output. This thesis uses the development of a histogram as a test case to investigate the efficiency of three different tools, HDL Coder in MATLAB, HDL Coder in Simulink and System Generator for DSP in comparison to the direct development of the same histogram in Vivado using Verilog. How to write and structure code in these tools for proper functionality was also examined. It has been found that all tools deliver an operation frequency comparable to a direct implementation in Verilog, decreased resource usage, a development time which decreased by 27% (HDL Coder in MATLAB), 45% (System Generator) and 64% (HDL Coder in Simulink) but at the cost of increased power consumption. Instructions for how to use all three tools has been collected and summarised. / I ingångssteget på ett mätsystem är det av intresse att använda en FPGA för att uppnå höga hastigheter på de oundvikliga datafiltrering och sorterings algoritmer som körs. Ett problem med FPGAer är att utvecklingen ställer höga krav på specifik kunskap gällande utvecklingsspråk och miljöer vilket för en person specialiserad inom t.ex. signalbehandling kan saknas helt. HLS är en metodik där högnivåspråk kan användas för digital design genom att nyttja ett verktyg för automatgenerering av kod. I detta arbete har utveckling av ett histogram använts som testfall för att utvärdera effektivitet samt designmetodik av tre olika HLS verktyg, HDL Coder till MATLAB, HDL Coder till Simulink och System Generator for DSP. Utvecklingen i dessa verktyg har jämförts mot utvecklingen av samma histogram i Vivado, där språket Verilog använts. Arbetets slutsater är att samtliga verktyg som testats leverar en arbetsfrekvens som är jämförbar med att skriva histogrammet direkt i Verilog, en minskad resursanvändning, utvecklingstid som minskat med 27% (HDL Coder i MATLAB), 45% (System Generator) och 64% (HDL Coder i Simulink) men med en ökad strömförbrukning. En sammanställning av instruktioner för utveckling med hjälp av verktygen har även gjorts.
97

Wordlength inference in the Spade HDL : Seven implementations of wordlength inference and one implementation that actually works / Ordlängdsinferans i Spade HDL : Sju olika implementationer av ordlängdsinferens och en implementation som faktiskt fungerar

Thörnros, Edvard January 2023 (has links)
Compilers, complex programs with the potential to greatly facilitate software and hardware design. This thesis focuses on enhancing the Spade hardware description language, known for its user-friendly approach to hardware design. In the realm of hardware development data size - for numerical values data size is known as "wordlength" - plays a critical role for reducing the hardware resources. This study presents an innovative approach that seamlessly integrates wordlength inference directly into the Spade language, enabling the over-estimation of numeric data sizes solely from the program's source code. The methodology involves iterative development, incorporating various smaller implementations and evaluations, reminiscent of an agile approach. To assess the efficacy of the wordlength inference, multiple place and route operations are performed on identical Spade code using various versions of nextpnr. Surprisingly, no discernible impact on hardware resource utilization emerges from the modifications introduced in this thesis. Nonetheless, the true significance of this endeavor lies in its potential to unlock more advanced language features within the Spade compiler. It is important to note that while the wordlength inference proposed in this thesis shows promise, it necessitates further integration efforts to realize its full potential.
98

High-Level-Synthese von Operationseigenschaften / High-Level Synthesis Using Operation Properties

Langer, Jan 12 December 2011 (has links) (PDF)
In der formalen Verifikation digitaler Schaltkreise hat sich die Methodik der vollständigen Verifikation anhand spezieller Operationseigenschaften bewährt. Operationseigenschaften beschreiben das Verhalten einer Schaltung in einem festen Zeitintervall und können sequentiell miteinander verknüpft werden, um so das Gesamtverhalten zu spezifizieren. Zusätzlich beweist eine formale Vollständigkeitsprüfung, dass die Menge der Eigenschaften für jede Folge von Eingangssignalwerten die Ausgänge der zu verifizierenden Schaltung eindeutig und lückenlos determiniert. In dieser Arbeit wird untersucht, wie aus Operationseigenschaften, deren Vollständigkeit erfolgreich bewiesen wurde, automatisiert eine Schaltungsbeschreibung abgeleitet werden kann. Gegenüber der traditionellen Entwurfsmethodik auf Register-Transfer-Ebene (RTL) bietet dieses Verfahren zwei Vorteile. Zum einen vermeidet der Vollständigkeitsbeweis viele Arten von Entwurfsfehlern, zum anderen ähnelt eine Beschreibung mit Hilfe von Operationseigenschaften den in Spezifikationen häufig genutzten Zeitdiagrammen, sodass die Entwurfsebene der Spezifikationsebene angenähert wird und Fehler durch manuelle Verfeinerungsschritte vermieden werden. Das Entwurfswerkzeug vhisyn führt die High-Level-Synthese (HLS) einer vollständigen Menge von Operationseigenschaften zu einer Beschreibung auf RTL durch. Die Ergebnisse zeigen, dass sowohl die verwendeten Synthesealgorithmen, als auch die erzeugten Schaltungen effizient sind und somit die Realisierung größerer Beispiele zulassen. Anhand zweier Fallstudien kann dies praktisch nachgewiesen werden. / The complete verification approach using special operation properties is an accepted methodology for the formal verification of digital circuits. Operation properties describe the behavior of a circuit during a certain time interval. They can be sequentially concatenated in order to specify the overall behavior. Additionally, a formal completeness check proves that the sequence of properties consistently determines the exact value of the output signals for every valid sequence of input signal values. This work examines how a circuit description can be automatically derived from a set of operation properties whose completeness has been proven. In contrast to the traditional design flow at register-transfer level (RTL), this method offers two advantages. First, the prove of completeness helps to avoid many design errors. Second, the design of operation properties resembles the design of timing diagrams often used in textual specifications. Therefore, the design level is closer to the specification level and errors caused by refinement steps are avoided. The design tool vhisyn performs the high-level synthesis from a complete set of operation properties to a description at RTL. The results show that both the synthesis algorithms and the generated circuit descriptions are efficient and allow the design of larger applications. This is demonstrated by means of two case studies.
99

Implementação de métrica de avaliação objetiva de qualidade de vídeo digital em lógica reconfigurável / Implementation of objective video quality metric in reconfigurable logic

Oliveira, Marcelo de 24 February 2017 (has links)
Conselho Nacional do Desenvolvimento Científico e Tecnológico (CNPq) / É implementado em hardware, por meio da linguagem VHDL, um método de avaliação objetiva de qualidade de vídeo digital. Sendo um processo computacionalmente custoso em software, investiga-se sua implementação em hardware. O método implementado, chamado de NRVQA-LM, utiliza seis características espaço-temporais extraídas de diferentes vídeos para chegar a um escore de qualidade. São estudadas essas características e planejada a sua implementação de forma otimizada, a fim de aproveitar as vantagens de plataformas de lógica reconfigurável, como as FPGAS. Durante o desenvolvimento foi necessário o estudo de ferramentas não usuais da linguagem VHDL, tais como as aritméticas de ponto fixo e flutuante e a escrita de funções matemáticas. Os resultados mostram alta correlação com os valores das características e dos escores de qualidade em relação ao método em software. A implementação se mostrou custosa em termos de recursos lógicos, especialmente devido à necessidade de se armazenar um quadro de vídeo inteiro, mas eficiente graças à característica de paralelismo das FPGAs, executando cálculos entre 20 e 40 vezes mais rapidamente que em uma linguagem de alto nível como o MATLAB. A aritmética ponto fixo mostrou-se vantajosa em relação ao ponto flutuante, principalmente no que tange à frequência de operação. / It is implemented in hardware an objective digital video evaluation method, using the VHDL language. As a computationally expensive process in software, it is investigated its implementation in a hardware platform. The implemented method, named NRVQA-LM, employs six spatio-temporal features extracted from different videos in order to obtain a quality score. These features are studied and the implementation is designed to be developed in an optimized way, in order to explore the benefits of reprogammable logic platforms, such as FPGAs. During the development it was necessary to study non-recurrent tools of the VHDL language, such as fixed- and floating-point arithmetics and the writing of math functions. Results shows high correlation between the calculated scores of the hardware and the original software implementations. The hardware implementation revealed to be highly resource expensive, mainly due the need of storing a whole video frame, but efficient in time, thanks to the parallelism feature of FPGA devices, executing quality score calculations between 20 and 40 times faster than a high-level language such as MATLAB. The fixed-point arithmetics revealed to be more efficient than the floating-point, specially regarding operation frequency.
100

Implementação de métrica de avaliação objetiva de qualidade de vídeo digital em lógica reconfigurável / Implementation of objective video quality metric in reconfigurable logic

Oliveira, Marcelo de 24 February 2017 (has links)
Conselho Nacional do Desenvolvimento Científico e Tecnológico (CNPq) / É implementado em hardware, por meio da linguagem VHDL, um método de avaliação objetiva de qualidade de vídeo digital. Sendo um processo computacionalmente custoso em software, investiga-se sua implementação em hardware. O método implementado, chamado de NRVQA-LM, utiliza seis características espaço-temporais extraídas de diferentes vídeos para chegar a um escore de qualidade. São estudadas essas características e planejada a sua implementação de forma otimizada, a fim de aproveitar as vantagens de plataformas de lógica reconfigurável, como as FPGAS. Durante o desenvolvimento foi necessário o estudo de ferramentas não usuais da linguagem VHDL, tais como as aritméticas de ponto fixo e flutuante e a escrita de funções matemáticas. Os resultados mostram alta correlação com os valores das características e dos escores de qualidade em relação ao método em software. A implementação se mostrou custosa em termos de recursos lógicos, especialmente devido à necessidade de se armazenar um quadro de vídeo inteiro, mas eficiente graças à característica de paralelismo das FPGAs, executando cálculos entre 20 e 40 vezes mais rapidamente que em uma linguagem de alto nível como o MATLAB. A aritmética ponto fixo mostrou-se vantajosa em relação ao ponto flutuante, principalmente no que tange à frequência de operação. / It is implemented in hardware an objective digital video evaluation method, using the VHDL language. As a computationally expensive process in software, it is investigated its implementation in a hardware platform. The implemented method, named NRVQA-LM, employs six spatio-temporal features extracted from different videos in order to obtain a quality score. These features are studied and the implementation is designed to be developed in an optimized way, in order to explore the benefits of reprogammable logic platforms, such as FPGAs. During the development it was necessary to study non-recurrent tools of the VHDL language, such as fixed- and floating-point arithmetics and the writing of math functions. Results shows high correlation between the calculated scores of the hardware and the original software implementations. The hardware implementation revealed to be highly resource expensive, mainly due the need of storing a whole video frame, but efficient in time, thanks to the parallelism feature of FPGA devices, executing quality score calculations between 20 and 40 times faster than a high-level language such as MATLAB. The fixed-point arithmetics revealed to be more efficient than the floating-point, specially regarding operation frequency.

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