ch14.4.htm

介绍asci设计的一本书

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14.4.7&nbsp;<A NAME="10337">
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Hardware Acceleration</H2>
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Simulation engines</SPAN>
 or <A NAME="marker=74438">
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hardware accelerators</SPAN>
 use computer architectures that are tuned to fault-simulation algorithms. These special computers allow you to add multiple simulation boards in one chassis. Since each board is essentially a workstation produced in relatively low volume and there are between 2 and 10 boards in one accelerator, these machines are between one and two orders of magnitude more expensive than a workstation. There are two ways to use multiple boards for fault simulation. One method runs good circuits on each board in parallel with the same stimulus and generates faulty circuits concurrently with other boards. The acceleration factor is less than the number of boards because of overhead. This method is usually faster than distributing a good circuit across multiple boards. Some fault simulators allow you to use multiple circuits across multiple machines on a network in <A NAME="marker=53930">
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distributed fault simulation</SPAN>
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Fault</P>
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Type</P>
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1</SUP>
Vectors (hex)</P>
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Good</P>
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output</P>
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Bad</P>
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output</P>
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F1</P>
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SA1</P>
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3</SPAN>
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0</P>
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1</P>
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F2</P>
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SA1</P>
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0, 4</P>
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0, 0</P>
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1, 1</P>
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F3</P>
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SA1</P>
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4, 5</P>
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0, 0</P>
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1, 1</P>
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F4</P>
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SA1</P>
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3</P>
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0 </P>
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1 </P>
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F5</P>
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SA1</P>
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2</P>
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