Logic Sniffer 103

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Run Length Encoding is a compression method that records the time between logic changes, instead of snapshot of the logic at each point in time.

  • A common issue is that sampling never ends. This will happen if there are no changes to record.
  • The highest channel is not available in RLE modes. It is used in the RLE protocol.
See updates for the v3 Demon Core that supports RLE

Sample width

The highest channel is not available in RLE modes. It is used in the RLE protocol to encode the sample as a no change measurement or a change measurement.

RLE sample widths
Groups NormalRLE
1 8bit7bit
2 16bit15bit
3 24bit 23bit
4 32bit31bit

Sample depth

RLE extends the total samples possible, but it will still use all the samples if there is no change in pin data.

Max RLE samples
Groups RLE bitsMAX samples*Duration at 100MHz
17bit1.5 million15ms
215bit196 million2 seconds
323bit67.1 billion
431bit6.4 trillion17.9 hours

MAX samples* based on:

  • (total sample width/2) * (max value for RLE bits) = max samples
  • (24K/2) * 128 = 1.5 million samples
  • (12K/2) * 32768 = 196 million samples
  • (8K/2) * = 67.1 billion samples
  • (6K/2) * 2147483647 = 6.4 trillion samples.


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