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941.
In this paper, we propose techniques for fast cycle-approximate multi-processor SoC simulation with timed transaction level
models and OS models. Cycle-approximate simulation with an abstract model is widely used for fast validation of a multi-processor
SoC in early design stages. However, the performance gain of abstract-level simulation is limited by the overhead of synchronizing
multiple concurrent processor/module simulators, which is inevitable in timed simulation. To reduce the synchronization overhead,
we adopt the synchronization time-point prediction method, which consists of two phases: static code analysis and dynamic
scheduling of synchronizations. In the static analysis phase before simulation, it estimates minimum execution time from every
point in the code to the nearest synchronization point. Then, during simulation, it pessimistically predicts the synchronization
time-points based on the estimates. The proposed approach targets fast cycle-approximate simulation of a system with delay
annotated SW code and transaction level models of HW with dynamic behavior. We present, in this paper, techniques to analyze
such abstract models of SW and HW and schedule minimal number synchronizations during cycle-approximate simulation of the
models. Experiments show that the approach achieves orders of magnitude higher performance in cycle-approximate multi-processor
SoC simulation. 相似文献
942.
943.
Nikolaos S. Voros Luis Sánchez Alejandro Alonso Alexios N. Birbas Michael Birbas Ahmed Jerraya 《Design Automation for Embedded Systems》2003,8(1):5-49
This paper presents a hardware/software co-design approachwhere different specification languages can be used in parallel, allowingeffective system co-modeling. The proposed methodology introduces a processmodel that extends the traditional spiral model so as to reflect the designneeds of modern embedded systems. The methodology is supported by an advancedtoolset that allows co-modeling and co-simulation using SDL, Statecharts andMATRIXX, and interactive hardware/software partitioning. The effectivenessof the proposed approach is exhibited through two applicati on examples: thedesign of a car window lift mechanism, and the design of a MAC layer protocolfor wireless ATM networks. 相似文献
944.
概述了埋入集成无源元件印制板以及它们的非真空加工和真空加工的选择,还讨论了埋入集成无源元件业务的拓展趋势。 相似文献
945.
946.
Avalon总线与SOPC系统架构实例 总被引:10,自引:0,他引:10
介绍了可编程系统集成(SOPC)的基本概念和Avalon总线,着重描述了Avalon总线的内容和操作,利用SOPC Builder搭建了一个SOPC的实例,在Altera的Excalibur Nios开发板上进行了仿真验证。 相似文献
947.
Neal Bambha Vida Kianzad Mukul Khandelia Shuvra S. Bhattacharyya 《Design Automation for Embedded Systems》2002,7(4):307-323
Self-timed scheduling is an attractive implementation style for multiprocessor DSP systems due to its ability to exploit predictability in application behavior, its avoidanceof over-constrained synchronization, and its simplified clocking requirements.However, analysis and optimization of self-timed systems under real-time constraintsis challenging due to the complex, irregular dynamics of self-timed operation.In this paper, we review a number of high-level intermediate representationsfor compiling dataflow programs onto self-timed DSP platforms, including representationsfor modeling the placement of interprocessor communication (IPC) operations;separating synchronization from data transfer during IPC; modeling and optimizinglinear orderings of communication operations; performing accurate design spaceexploration under communication resource contention; and exploring alternativeprocessor assignments during the synthesis process. We review the structureof these representations, and discuss efficient techniques that operate onthem to streamline scheduling, communication synthesis, and power managementof multiprocessor DSP implementations. 相似文献
948.
949.
基于DCT变换的内嵌静止图像压缩算法 总被引:9,自引:0,他引:9
提出了一种有效的基于离散余弦变换(DCT)的内嵌子带图像编码算法.Xiong等人提出的EZDCT算法采用零树结构实现了一种内嵌DCT编码器,且其性能优于JPEG.本文指出DCT的零树结构在内嵌DCT算法中并非很有效,同时提出了一种不依赖零树结构的简便、高效的内嵌DCT子带编码算法.实验结果表明本文算的压缩性能(PSNR)比EZDCT高约0.5~1.5dB,且接近当前最通用的内嵌小波SPIHT算法,在对某些图像压缩时还优于SPIHT算法. 相似文献
950.
R. Govindarajan Erik R. Altman Guang R. Gao 《Design Automation for Embedded Systems》2002,6(3):243-275
Exploiting instruction-level parallelism (ILP) is extremely important for achieving high performance in application specific instruction set processors (ASIPs) and embedded processors. Unlike conventional general purpose processors, ASIPs and embedded processors typically run a single application and hence must be optimized extensively for this in order to extract maximum performance. Further, low power and low cost requirements of ASIPs may demand reuse of pipeline stages causing pipelines with complex structural hazards. In such architectures, exploiting higher ILP is a major challenge to the designer.Existing techniques deal with either scheduling hardware pipelines to obtain higher throughput or software pipelining—an instruction scheduling technique for iterative computation—for exploiting greater ILP. We integrate these techniques to co-schedule hardware and software pipelines to achieve greater instruction throughput. In this paper, we develop the underlying theory of Co-Scheduling, called the Modulo-Scheduled Pipeline (or MS-Pipeline) theory. More specifically, we establish the necessary and sufficient condition for achieving the maximum throughput in a given pipeline operating under modulo scheduling. Further, we establish a sufficient condition to achieve a specified throughput, based on which we also develop a methodology for designing the hardware pipelines that achieve such a throughput. Further, we present initial experimental results which help to establish the usefulness of MS-pipeline theory in software pipelining. As the proposed theory helps to analyze and improve the throughput of Modulo-Scheduled Pipelines (MS-pipelines), it is especially useful in designing ASIPs and embedded processors. 相似文献