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0 pointsRetr0id6d ago0 comments

But you can't use equivalent-time sampling for something non-repetitive like network packets.

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For measurements like this the SDK will usually include some utilities to send the same data over and over on a port.

Even if it's the same data, the bit stream will be a variety of 0 and 1s. The period of that waveform will then be 1 frame length / data transfer rate (or rather 1/4 frame length / data transfer rate as this is a QSGMII link). I wonder how the scope triggers on that. Trigger criterium would be a bit pattern, say the Ethernet frame preamble of 7 octects (* 10/8) spread across four streams ...

Otoh, at 5Gbps, a sample rate of "just" 10GS/s would be sufficient (barely).

I rather suspect the oscilloscope is capable of 1TS/s equivalent time sampling, but that mode wasn't used.

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Aurornis6d ago

For measurements like this the SDK will usually include some utilities to send the same data over and over on a port.

guenthert6d ago

Otoh, at 5Gbps, a sample rate of "just" 10GS/s would be sufficient (barely).

I rather suspect the oscilloscope is capable of 1TS/s equivalent time sampling, but that mode wasn't used.

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