ADP3450 record mode sample rate and dropping samples

[cprosser]

Hi Folks,

I have an ADP3450 connected via a dedicated ethernet port on my computer. When I run the speed test it reports:
To Device: 0.142ms 57.59MiBps
From Device: 0.1414ms 71.105MiBps 4 MiB

I'm having a problem with the Scope in record mode. I'm running at 1MHz sample rate and any attempt to capture >1M samples fails by losing all the scope samples and reporting "Samples were lost. reduce sampling rate".

This is Beta 3.17.21. I'm on Win 11 on decent machine (i5-12600K). That big spike at the end is surprising (and exceeds the speed test numbers).

I've attached the network utilization profile.

--chris
ofile for the dedicated ethernet port. It looks off to me.

[attila]

Hi @cprosser

In Standard mode it buffers up to 128Mi samples and transfers it when the capture is done.
Make sure to update the device fw if prompted, since version 3.17.19 fixes recording glitch over Eth when USB is not connected.
Try to reset the device by toggling the power switch.

[cprosser]

@attila thanks for the tip about the firmware! Looks like I was not being prompted to update the firmware since I had an ethernet only connection. I switched to USB only and I got the prompt in the device manager. Working great now.

Edit: Actually, still doesn't work correctly over ethernet though USB is working fine. I rolled back to 3.17.1 to see if it was a beta issue or not. I have the ethernet pretty locked down (no internet access, just access to my pc and that's it). Let me see if changing that helps.

Edited December 20, 2021 by cprosser

[cprosser]

Hmm. Found another firmware update (now on h340) but that didn't help. Ethernet (even with USB connected) still doesn't cache and forward correctly. On USB the % sample/prefill works correctly. On ethernet it never shows up and just says "Recording", and the returns an empty screen when done.

 

[attila]

Hi @cprosser

I was unable to reproduce this issue so far.

You could try the Linux boot mode. This has slightly lower performance, lacks DDR buffering, but it may have better compatibility than the Standard mode firmware with LwIP.

[cprosser]

Can't reproduce the bug? That sounds like a challenge :-)

I spent a little bit more time poking at it. It looks like it only occurs when you have two or fewer channels. You can see the attached video how the problem goes away when I switch it to three channels. I also tried lowering my ethernet connection speed to 100 Mb per second full duplex, that did not impact the behavior at all.

One thing I've noticed between USB versus ethernet mode is that USB provides more status updates. For instance when recording it provides prefill percentage in USB, but ethernet the pre-fill is not reported. Don't know if that's expected behavior or not.

[attila]

Hi @cprosser

I've managed to reproduce and fix it.

With the current software version uncheck the Options/"Acquire Noise" (or Noise under Config) to prevent this error.

Thank you for the observation.

[cprosser]

Great news. I had no idea how that function worked. Found your other post here:

and now have a better idea of how the device functions.