SignalTap Selective Sampling

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I'm trying to sample my signals, the problem is I don't have enough ram blocks in my DE2 board to capture for long enough, so I though may be I can capture selectively.

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A feature available in the last couple of Quartus versions might help. From the QII 8.0 handbook, Volume 3, Section V, Chapter 14:

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The custom state-based triggering flow allows for more efficient use of the space available in the acquisition buffer because only specific samples of interest are captured.

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