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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.
11

A Lightweight Processor Core for Application Specific Acceleration

Grant, David January 2004 (has links)
Advances in configurable logic technology have permitted the development of low-cost, high-speed configurable devices, allowing one or more soft processor cores to be introduced into a configurable computing system. Soft processor cores offer logic-area savings and reduced configuration times when compared to the hardware-only implementations typically used for application specific acceleration. Programs for a soft processor core are small and simple compared to the design of a hardware core, but can leverage custom hardware within the processor core to provide greater acceleration for specific applications. This thesis presents several configurable system models, and implements one such model on a Nios Embedded Processor Development Board. A software programmable and hardware configurable lightweight processor core known as the FAST CPU is introduced. The configurable system implementation attaches several FAST CPUs to a standard Nios processor to create a system for experimentation with application specific acceleration. This system incorporating the FAST CPUs was tested for bus utilization behaviour, computing performance, and execution times for a minheap application. Experimental results are compared to the performance of a software-only solution, and also with previous research results. Experimental results verify that the theory and models used to predict bus utilization are correct. Performance testing shows that the FAST CPU is approximately 25% slower than a general purpose processor, which is expected. The FAST CPU, however, is 31% smaller in terms of logic area than the general purpose processor, and is 8% smaller than the design of a hardware-only implementation of a minheap for application specific acceleration. The results verify that it is possible to move functionality from a general purpose processor to a lightweight processor, and further, to realize an increase in performance when a task is parallelized across multiple FAST CPUs. The experimentation uses a procedure by which a set of equations can be derived for predicting bus utilization and deriving a cost-benefit curve for a coprocessing entity. They are applied to a specific system in this research, but the methods are generalizable to any coprocessing entity.
12

A Lightweight Processor Core for Application Specific Acceleration

Grant, David January 2004 (has links)
Advances in configurable logic technology have permitted the development of low-cost, high-speed configurable devices, allowing one or more soft processor cores to be introduced into a configurable computing system. Soft processor cores offer logic-area savings and reduced configuration times when compared to the hardware-only implementations typically used for application specific acceleration. Programs for a soft processor core are small and simple compared to the design of a hardware core, but can leverage custom hardware within the processor core to provide greater acceleration for specific applications. This thesis presents several configurable system models, and implements one such model on a Nios Embedded Processor Development Board. A software programmable and hardware configurable lightweight processor core known as the FAST CPU is introduced. The configurable system implementation attaches several FAST CPUs to a standard Nios processor to create a system for experimentation with application specific acceleration. This system incorporating the FAST CPUs was tested for bus utilization behaviour, computing performance, and execution times for a minheap application. Experimental results are compared to the performance of a software-only solution, and also with previous research results. Experimental results verify that the theory and models used to predict bus utilization are correct. Performance testing shows that the FAST CPU is approximately 25% slower than a general purpose processor, which is expected. The FAST CPU, however, is 31% smaller in terms of logic area than the general purpose processor, and is 8% smaller than the design of a hardware-only implementation of a minheap for application specific acceleration. The results verify that it is possible to move functionality from a general purpose processor to a lightweight processor, and further, to realize an increase in performance when a task is parallelized across multiple FAST CPUs. The experimentation uses a procedure by which a set of equations can be derived for predicting bus utilization and deriving a cost-benefit curve for a coprocessing entity. They are applied to a specific system in this research, but the methods are generalizable to any coprocessing entity.
13

Design of Robust and Flexible On-chip Analog-to-Digital Conversion Architecture

Kim, Daeik D. 17 August 2004 (has links)
This dissertation presents a comprehensive design and analysis framework for system-on-a-chip analog-to-digital conversion design. The design encompasses a broad class of systems, which take advantage of system-on-a-chip complexity. This class is exemplified by an interferometric photodetector array based bio-optoelectronic sensor that is built and tested as part of the reported work. While there have been many discussions of the technical details of individual analog-to-digital converter (ADC) schemes in the literature, the importance of the analog front-end as a pre-processor for a data converter and the generalized analysis including converter encoding and decoding functions have not previously been investigated thoroughly, and these are key elements in the choice of converter designs for low-noise systems such as bio-optoelectronic sensors. Frequency domain analog front-end models of ADCs are developed to enable the architectural modeling of ADCs. The proposed models can be used for ADC statistically worst-case performance estimation, with stationary random process assumptions on input signals. These models prove able to reveal the architectural advantages of a specific analog-to-digital converter schemes quantitatively, allowing meaningful comparisons between converter designs. The modeling of analog-to-digital converters as communication channels and the ADC functional analysis as encoders and decoders are developed. This work shows that analog-to-digital converters can be categorized as either a decoder-centered design or an encoder-centered design. This perspective helps to show the advantages of nonlinear decoding schemes for oversampling noise-shaping data converters, and a new nonlinear decoding algorithm is suggested to explore the optimum solution of the decoding problem. A case study of decoder-centered and encoder-centered data converter designs is presented by applying the proposed theoretical framework. The robustness and flexibility of the resulting analog-to-digital converters are demonstrated and compared. The electrical and optical sensitivity measurements of a fabricated oversampling noise shaping analog-to-digital converter circuit are provided, and a sensor system-on-a-chip using these ADCs with integrated interferometric waveguides for bio-optoelectronic sensing is demonstrated.
14

Hardware/Software Deadlock Avoidance for Multiprocessor Multiresource System-on-a-Chip

Lee, Jaehwan 23 November 2004 (has links)
This thesis describes fast and deterministic deadlock avoidance methods that are easily applicable to real-time MultiProcessor System-on-a-Chip (MPSoC) design. This thesis first describes the proofs of the correctness of Parallel Deadlock Detection Algorithm (PDDA) and the run-time complexity of its hardware implementation in the Deadlock Detection Unit (DDU), proposed previously. The DDU has a worst-case run-time of O(min(m,n)) where m and n are the numbers of resources and processes, respectively. This thesis also provides detailed explanation and mathematical analysis of PDDA and the DDU along with examples, as well as extensive performance comparisons among PDDA in software, the DDU and an O(m x n) deadlock detection algorithm. The DDU is 100X or more faster than software implementations of deadlock detection algorithms. This thesis secondly proposes a novel deadlock avoidance algorithm and its hardware implementation in the Deadlock Avoidance Unit (DAU) that provides very fast and automatic deadlock avoidance in an MPSoC with multiple single-instance resources. The DAU avoids deadlock by not allowing any grant or request that leads to a deadlock. In case of livelock in an attempt to avoid deadlock, the DAU asks one of the processes involved in the livelock to release resource(s) so that such a livelock can also be resolved. We simulated two synthetic applications that can benefit from the DAU and demonstrated that the DAU avoids deadlock approximately 300X faster than its software implementation does. This thesis also proposes a novel Parallel Bankers Algorithm (PBA), a parallelized version of the Banker's Algorithm, and its hardware implementation in PBA Unit (PBAU) that provides fast, automatic deadlock avoidance for multiple-instance resource systems. The run-time complexity of the PBA is O(n) with the best case of O(1). The PBAU is about 1000X faster than the Banker's Algorithm in software and achieves in a particular example a 19% speed-up of application execution time. We believe that our approaches initiate a paradigm shift in the context of deadlock solutions for MPSoC from sole software to hardware/software partitioned solutions that enable a distribution of part of the burden imposed on processors to a low cost, fast hardware IP core exploiting full parallelism.
15

The Development Environment of Embedded System based on AMBA Platform

Wang, Wei-Cheng 23 January 2003 (has links)
In this paper, we proposed a hardware development environment of the Embedded system to reduce the complexity of the Embedded system archeitecture, fit the varied specification, decrease the difficulties and time consuming on hardware integration, and short the life period of products. According to the On-Cihp Bus platform, we can utilize certain modules repeatly and recofigure the parameters flexibily to integrate the necessary system hardware and complete the system verification rapidly that we can achieve the time to market. In this thesis, we discuss architecture of hardware platform and the technique of system integration. Further more; we introduce the concept of VRM (Verification Reuse Methodology) on the system verification that reduces the verification time of system.
16

A Low-Cost SoC for Information Appliance Networking

Chen, Zhao-Jung 09 October 2002 (has links)
In this paper, we will provide an example of SoC for Information Appliance. We will use the SoC to reduce design-time and design-cost for IA products. Simultaneously, we will also enhance the Gigabit Ethernet Media- Access-Controller (MAC) with Hardware TCP/IP Checksum module. It can alleviate the CPU loads effectively, especially in longer length packets.
17

Probabilistic boolean logic, arithmetic and architectures

Chakrapani, Lakshmi Narasimhan 25 August 2008 (has links)
Parameter variations, noise susceptibility, and increasing energy dissipation of CMOS devices have been recognized as major challenges in circuit and micro-architecture design in the nanometer regime. Among these, parameter variations and noise susceptibility are increasingly causing CMOS devices to behave in an "unreliable" or "probabilistic" manner. To address these challenges, a shift in design paradigm, from current day deterministic designs to "statistical" or "probabilistic" designs is deemed inevitable. Motivated by these considerations, I introduce and define probabilistic Boolean logic, whose logical operators are by definition "correct" with a probability 1/2 <= p <= 1. While most of the laws of conventional Boolean logic can be naturally extended to be valid in the probabilistic case, there are a few significant departures. We also show that computations realized using implicitly probabilistic Boolean operators are more energy efficient than their counterparts which use explicit sources of randomness, in the context of probabilistic Boolean circuits as well as probabilistic models with state, Rabin automata. To demonstrate the utility of implicitly probabilistic elements, we study a family of probabilistic architectures: the probabilistic system-on-a-chip PSOC, based on CMOS devices rendered probabilistic due to noise, referred to as probabilistic CMOS or PCMOS devices. These architectures yield significant improvements, both in the energy consumed as well as in the performance in the context of probabilistic or randomized applications with broad utility. Finally, we extend the consideration of probability of correctness to arithmetic operations, through probabilistic arithmetic. We show that in the probabilistic context, substantial savings in energy over correct arithmetic operations may be achieved. This is the theoretical basis of the energy savings reported in the video decoding and radar processing applications that has been demonstrated in prior work.
18

Núcleos de interface de memória DDR SDRAM para sistemas-em-chip

Bonatto, Alexsandro Cristóvão January 2009 (has links)
Dispositivos integrados de sistemas-em-chip (SoC), especialmente aqueles dedicados às aplicações multimídia, processam grandes quantidades de dados armazenados em memórias. O desempenho das portas de memória afeta diretamente no desempenho do sistema. A melhor utilização do espaço de armazenamento de dados e a redução do custo e do consumo de potência dos sistemas eletrônicos encorajam o desenvolvimento de arquiteturas eficientes para controladores de memória. Essa melhoria deve ser alcançada tanto para interfaces com memórias internas quanto externas ao chip. Em sistemas de processamento de vídeo, por exemplo, memórias de grande capacidade são necessárias para armazenar vários quadros de imagem enquanto que os algoritmos de compressão fazem a busca por redundâncias. No caso de sistemas implementados em tecnologia FPGA é possível utilizar os blocos de memória disponíveis internamente ao FPGA, os quais são limitados a poucos mega-bytes de dados. Para aumentar a capacidade de armazenamento de dados é necessário usar elementos de memória externa e um núcleo de propriedade intelectual (IP) de controlador de memória é necessário. Contudo, seu desenvolvimento é uma tarefa muito complexa e nem sempre é possível utilizar uma solução "sob demanda". O uso de FPGAs para prototipar sistemas permite ao desenvolvedor integrar módulos rapidamente. Nesse caso, a verificação do projeto é uma questão importante a ser considerada no desenvolvimento de um sistema complexo. Controladores de memória de alta velocidade são extremamente sensíveis aos atrasos de propagação da lógica e do roteamento. A síntese a partir de uma descrição em linguagem de hardware (HDL) necessita da verificação de sua compatibilidade com as especificações de temporização pré-determinadas. Como solução para esse problema, é apresentado nesse trabalho um IP do controlador de memória DDR SDRAM com função de BIST (Built-In Self-Test) integrada, onde o teste de memória é utilizado para verificar o funcionamento correto do controlador. / Many integrated Systems-on-Chip (SoC) devices, specially those dedicated to multimedia applications, process large amounts of data stored on memories. The performance of the memories ports directly affects the performance of the system. Optimization of the usage of data storage and reduction of cost and power consumption of the electronic systems encourage the development of efficient architectures for memory controllers. This improvement must be reached either for embedded or external memories. In systems for video processing, for example, large memory arrays are needed to store several video frames while compression algorithms search for redundancies. In the case of FPGA system implementation, it is possible to use memory blocks available inside FPGA, but for only a few megabytes of data. To increase data storage capacity it is necessary to use external memory devices and a memory controller intellectual property (IP) core is required. Nevertheless, its development is a very complex task and it is not always possible to have a custom solution. Using FPGA for system prototyping allows the developer to perform rapid integration of modules to exercise a hardware version. In this case, test is an important issue to be considered in a complex system design. High speed memory controllers are very sensitive to gate and routing delays and the synthesis from a hardware description language (HDL) needs to be verified to comply with predefined timing specifications. To overcome these problems, a DDR SDRAM controller IP was developed which integrate the BIST (Built-In Self-Test) function, where the memory test is used to check the correct functioning of the DDR controller.
19

Núcleos de interface de memória DDR SDRAM para sistemas-em-chip

Bonatto, Alexsandro Cristóvão January 2009 (has links)
Dispositivos integrados de sistemas-em-chip (SoC), especialmente aqueles dedicados às aplicações multimídia, processam grandes quantidades de dados armazenados em memórias. O desempenho das portas de memória afeta diretamente no desempenho do sistema. A melhor utilização do espaço de armazenamento de dados e a redução do custo e do consumo de potência dos sistemas eletrônicos encorajam o desenvolvimento de arquiteturas eficientes para controladores de memória. Essa melhoria deve ser alcançada tanto para interfaces com memórias internas quanto externas ao chip. Em sistemas de processamento de vídeo, por exemplo, memórias de grande capacidade são necessárias para armazenar vários quadros de imagem enquanto que os algoritmos de compressão fazem a busca por redundâncias. No caso de sistemas implementados em tecnologia FPGA é possível utilizar os blocos de memória disponíveis internamente ao FPGA, os quais são limitados a poucos mega-bytes de dados. Para aumentar a capacidade de armazenamento de dados é necessário usar elementos de memória externa e um núcleo de propriedade intelectual (IP) de controlador de memória é necessário. Contudo, seu desenvolvimento é uma tarefa muito complexa e nem sempre é possível utilizar uma solução "sob demanda". O uso de FPGAs para prototipar sistemas permite ao desenvolvedor integrar módulos rapidamente. Nesse caso, a verificação do projeto é uma questão importante a ser considerada no desenvolvimento de um sistema complexo. Controladores de memória de alta velocidade são extremamente sensíveis aos atrasos de propagação da lógica e do roteamento. A síntese a partir de uma descrição em linguagem de hardware (HDL) necessita da verificação de sua compatibilidade com as especificações de temporização pré-determinadas. Como solução para esse problema, é apresentado nesse trabalho um IP do controlador de memória DDR SDRAM com função de BIST (Built-In Self-Test) integrada, onde o teste de memória é utilizado para verificar o funcionamento correto do controlador. / Many integrated Systems-on-Chip (SoC) devices, specially those dedicated to multimedia applications, process large amounts of data stored on memories. The performance of the memories ports directly affects the performance of the system. Optimization of the usage of data storage and reduction of cost and power consumption of the electronic systems encourage the development of efficient architectures for memory controllers. This improvement must be reached either for embedded or external memories. In systems for video processing, for example, large memory arrays are needed to store several video frames while compression algorithms search for redundancies. In the case of FPGA system implementation, it is possible to use memory blocks available inside FPGA, but for only a few megabytes of data. To increase data storage capacity it is necessary to use external memory devices and a memory controller intellectual property (IP) core is required. Nevertheless, its development is a very complex task and it is not always possible to have a custom solution. Using FPGA for system prototyping allows the developer to perform rapid integration of modules to exercise a hardware version. In this case, test is an important issue to be considered in a complex system design. High speed memory controllers are very sensitive to gate and routing delays and the synthesis from a hardware description language (HDL) needs to be verified to comply with predefined timing specifications. To overcome these problems, a DDR SDRAM controller IP was developed which integrate the BIST (Built-In Self-Test) function, where the memory test is used to check the correct functioning of the DDR controller.
20

Núcleos de interface de memória DDR SDRAM para sistemas-em-chip

Bonatto, Alexsandro Cristóvão January 2009 (has links)
Dispositivos integrados de sistemas-em-chip (SoC), especialmente aqueles dedicados às aplicações multimídia, processam grandes quantidades de dados armazenados em memórias. O desempenho das portas de memória afeta diretamente no desempenho do sistema. A melhor utilização do espaço de armazenamento de dados e a redução do custo e do consumo de potência dos sistemas eletrônicos encorajam o desenvolvimento de arquiteturas eficientes para controladores de memória. Essa melhoria deve ser alcançada tanto para interfaces com memórias internas quanto externas ao chip. Em sistemas de processamento de vídeo, por exemplo, memórias de grande capacidade são necessárias para armazenar vários quadros de imagem enquanto que os algoritmos de compressão fazem a busca por redundâncias. No caso de sistemas implementados em tecnologia FPGA é possível utilizar os blocos de memória disponíveis internamente ao FPGA, os quais são limitados a poucos mega-bytes de dados. Para aumentar a capacidade de armazenamento de dados é necessário usar elementos de memória externa e um núcleo de propriedade intelectual (IP) de controlador de memória é necessário. Contudo, seu desenvolvimento é uma tarefa muito complexa e nem sempre é possível utilizar uma solução "sob demanda". O uso de FPGAs para prototipar sistemas permite ao desenvolvedor integrar módulos rapidamente. Nesse caso, a verificação do projeto é uma questão importante a ser considerada no desenvolvimento de um sistema complexo. Controladores de memória de alta velocidade são extremamente sensíveis aos atrasos de propagação da lógica e do roteamento. A síntese a partir de uma descrição em linguagem de hardware (HDL) necessita da verificação de sua compatibilidade com as especificações de temporização pré-determinadas. Como solução para esse problema, é apresentado nesse trabalho um IP do controlador de memória DDR SDRAM com função de BIST (Built-In Self-Test) integrada, onde o teste de memória é utilizado para verificar o funcionamento correto do controlador. / Many integrated Systems-on-Chip (SoC) devices, specially those dedicated to multimedia applications, process large amounts of data stored on memories. The performance of the memories ports directly affects the performance of the system. Optimization of the usage of data storage and reduction of cost and power consumption of the electronic systems encourage the development of efficient architectures for memory controllers. This improvement must be reached either for embedded or external memories. In systems for video processing, for example, large memory arrays are needed to store several video frames while compression algorithms search for redundancies. In the case of FPGA system implementation, it is possible to use memory blocks available inside FPGA, but for only a few megabytes of data. To increase data storage capacity it is necessary to use external memory devices and a memory controller intellectual property (IP) core is required. Nevertheless, its development is a very complex task and it is not always possible to have a custom solution. Using FPGA for system prototyping allows the developer to perform rapid integration of modules to exercise a hardware version. In this case, test is an important issue to be considered in a complex system design. High speed memory controllers are very sensitive to gate and routing delays and the synthesis from a hardware description language (HDL) needs to be verified to comply with predefined timing specifications. To overcome these problems, a DDR SDRAM controller IP was developed which integrate the BIST (Built-In Self-Test) function, where the memory test is used to check the correct functioning of the DDR controller.

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