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Some embedded designers get frustrated when the performance of their selected FPGA embedded processor is half or less of what was expected based on published performance numbers. In some cases, a designer is unable to duplicate the manufacturer's published results for a benchmark. The reason often lies with the designer's lack of understanding of how these benchmarks are produced, but it can also reflect a lack of experience with the specific processor being used and the available techniques for...

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Some embedded designers get frustrated when the performance of their selected FPGA embedded processor is half or less of what was expected based on published performance numbers. In some cases, a designer is unable to duplicate the manufacturer's published results for a benchmark. The reason often lies with the designer's lack of understanding of how these benchmarks are produced, but it can also reflect a lack of experience with the specific processor being used and the available techniques for...

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Some embedded designers get frustrated when the performance of their selected FPGA embedded processor is half or less of what was expected based on published performance numbers. In some cases, a designer is unable to duplicate the manufacturer's published results for a benchmark. The reason often lies with the designer's lack of understanding of how these benchmarks are produced, but it can also reflect a lack of experience with the specific processor being used and the available techniques for...

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As you've learned in the early chapters of this book, the Field-Programmable Gate Array (FPGA) is a general-purpose device filled with digital logic building blocks. The two market leaders in the FPGA industry, Altera and Xilinx, are the focus of this discussion, although other programmable logic companies do exist, including Actel, Quicklogic, and Lattice Semiconductor. The most primitive FPGA building block is called either a logic cell (LC) by Xilinx or a logic element (LE) by Altera. In eith...

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As you've learned in the early chapters of this book, the Field-Programmable Gate Array (FPGA) is a general-purpose device filled with digital logic building blocks. The two market leaders in the FPGA industry, Altera and Xilinx, are the focus of this discussion, although other programmable logic companies do exist, including Actel, Quicklogic, and Lattice Semiconductor. The most primitive FPGA building block is called either a logic cell (LC) by Xilinx or a logic element (LE) by Altera. In eith...

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Reducing Size by Introducing a Loop Array Splitting Improving Streaming Performance Loop Unrolling Pipelining the Main Loop

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Reducing Size by Introducing a Loop Array Splitting Improving Streaming Performance Loop Unrolling Pipelining the Main Loop

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Fundamentally, an FPGA provides the opportunity to create arbitrary hardware structures and to connect these structures using a switched fabric of programmable interconnects. The flexibility of such a platform creates enormous opportunities for increasing the performance of algorithmsin particular, algorithms that can make use of parallelism. Without an efficient and semi-automated way to compile higher-level algorithms to equivalent lower-level hardware structures, however, the rapid creation...

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Fundamentally, an FPGA provides the opportunity to create arbitrary hardware structures and to connect these structures using a switched fabric of programmable interconnects. The flexibility of such a platform creates enormous opportunities for increasing the performance of algorithmsin particular, algorithms that can make use of parallelism. Without an efficient and semi-automated way to compile higher-level algorithms to equivalent lower-level hardware structures, however, the rapid creation...

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Experimenting with mixed hardware/software solutions can be a time-consuming process due to the historical disconnect between software development methods and the lower-level methods required for hardware design, including design for FPGAs. For many applications, the complete hardware/software design is represented by a collection of software and hardware source files that are not easily compiled, simulated, or debugged with a single tool set. In addition, because the hardware design process is ...

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As the line between what is hardware and what is software continues to blur, the skill sets of the hardware engineer and the software engineer have begun to merge. Hardware engineers have embraced language-based design (HDLs are simply a way to abstract a certain class of hardware as a written description). Software engineersin particular, those developing embedded, multiprocessor applicationshave started to introduce important hardware-oriented concepts such as concurrency and message-driven pr...

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Because of their reprogrammability, designing for FPGAs is conceptually similar to designing for common embedded processors. Simulation tools can be used to debug and verify the functionality of an application prior to actually programming a physical device, and there are tools readily available from FPGA vendors for performing in-system debugging. Although the tools are more complex and design processing times are substantially longer (it can take literally hours to process a large application ...

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Software development tools, whether intended for deeply embedded systems or for enterprise applications, add value and improve the results of the application development process in two fundamental ways. First, a good set of tools provides an appropriate and easily understood abstraction of a target platform (whether an embedded processor, a desktop PC, or a supercomputer). A good abstraction of the platform allows software developers to create, test, and debug relatively portable applications wh...

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The decision to add an FPGA to a new or existing embedded system may be driven by the desire to extend the usefulness of a common, low-cost microprocessor (and avoid introducing a higher-end, specialized processor such as a DSP chip) or to eliminate the need for custom ASIC processing functions. In cases where the throughput of an existing system must increase to handle higher resolutions or larger signal bandwidths, the required performance increases may be primarily computational (requiring a ...

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A field-programmable gate array (FPGA) is a large-scale integrated circuit that can be programmed after it is manufactured rather than being limited to a predetermined, unchangeable hardware function. The term "field-programmable" refers to the ability to change the operation of the device "in the field," while "gate array" is a somewhat dated reference to the basic internal architecture that makes this after-the-fact reprogramming possible. FPGAs come in a wide variety of sizes and with many di...

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