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I received an unexpected overflow error with a burst size smaller than 256 or 512 samples. What happens?

I received an unexpected overflow error with a burst size smaller than 256 or 512 samples. What happens?

This issue was detected and affects Exostiv Dashboard software up to version 1.7.x. *** Status – solved : please update software to version 1.8.x. ***

Under the circumstances described hereafter, an unexpected overflow is reported – which sometimes creates a software crash.
This combination of conditions actually creates an overflow condition in EXOSTIV Prove, whereas the bandwidth should be sufficient to handle the capture.

  • 1. The overall bandwidth can be saturated. It means that you are trying to sample data than require more bandwidth than what is available at the transceivers level. In other words, there will be an overflow condition if you sample data continuously.
  • 2. The burst size that you are trying to collect is below 256 or 512 samples.
  • 3. You are using more than 1 transceiver. For 2 transceivers, the issue appears for bursts of 32 samples; for 3 transceivers, the issue appears for bursts of 32 and 64 samples; for 4 transceivers, the issue appears for bursts of 32, 64 and 128 samples.
    These numbers seem to be doubled if you use a 12 Gbps probe.

Augmenting the number of samples per burst works around this problem.
In all cases, capturing bursts sizes at least equal to 256 samples with a 6 Gbps probe and at least equal to 512 samples with a 12 Gbps probe solves the problem.

*** Status – solved : please update software to version 1.8.x. ***

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