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Simple way to show ethernet packet timing on scope
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mikeselectricstuff:
Is there a simple way to see the duration and timing of 100Mbps ethernet packets on a scope ?
I'm trying to get a feel for timings when receiving UDP data with a W5500, and would like to see the timing of the packets on the wire relative to when I get an interrupt 
Scoping the Rx pins on the magjack just shows a random-ish waveform with no obvious pattern regardless of whether it's idle or transferring. I do have control over packet content so can transmit specific byte values.
Nusa:
I believe it's a differential signal, which means you either need a differential probe or you need to set up two scope channels to get a similar result.
mikeselectricstuff:

--- Quote from: Nusa on July 23, 2018, 05:51:07 pm ---I believe it's a differential signal, which means you either need a differential probe or you need to set up two scope channels to get a similar result.

--- End quote ---
It's differential but driven symmetrically, so looking at one line gives you all the info.
Kjelt:
Packet timing? Why a scope?
Just a cheap portmirroring networkswitch and a laptop with wireshark and you get the timing of your packets.
If you want flank-timing its more difficult, no idea but this looks interesting using a diff probe and tek scope with ethernet bus decoding built in
mikeselectricstuff:

--- Quote from: Kjelt on July 23, 2018, 05:58:14 pm ---Packet timing? Why a scope?
Just a cheap portmirroring networkswitch and a laptop with wireshark and you get the timing of your packets.

--- End quote ---
That doesn't show the relative timing to me pulling the packets out of the W5500, nor the length ( though that could be calculated). I basically want to know how fast packets can be sent before any get missed, and this is a function of several things, like W5500 latency, buffer size and how fast I can pull the data out.

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